Problems

61 of 61 problems

• Tow only

  Cracked weld on the rear axle housing

  A small group of owner reports filed with the United States road safety agency describes something that does not appear on most fault lists for this truck: welds on the rear axle housing cracking and separating, with gear oil escaping along the seam, the wheel on that side no longer standing square, and owners describing the wheel as heading for separation. One of them describes the housing as having separated at the weld three quarters of the way around. There is no recall behind this and no factory bulletin cited here — it is a pattern in owner reports, several of them, describing the same failure in the same place. **Every one of those reports is from a single model year**, and the fitment above is deliberately narrowed to it rather than spread across the generation: the evidence says what it says, and no more. If your truck is an adjacent year, the inspection below is still worth ten minutes, but nothing here claims your year is affected. That scoping, and the absence of any bulletin, is why the entry sits at community-consensus rather than carrying documentary authority. The reason it says tow rather than drive carefully is that the failure has no useful middle. An axle housing is what holds the wheel at the right angle to the road and keeps the differential's gears in mesh; when it is cracked, load is being carried by less metal every kilometre, and the failure that ends it is a wheel going somewhere the truck is not. If you find a wet seam along a weld on the axle, or a rear wheel that has started leaning, the sensible next move is a flatbed and a qualified mechanic looking at it on a hoist, not a careful drive to the workshop.

  DrivetrainSafety-critical

  • Gear oil weeping along a seam or a weld on the rear axle housing
  • One rear wheel visibly leaning where the other stands square
  • A clunk and a change in how the truck tracks when power comes on
  • A visible crack, or a bright line of clean metal, along a weld on the housing
  • A rear tyre that has suddenly started wearing on one edge only

• Do not drive

  ABS lamp on and wheels locking in a hard stop

  The second generation's multi-mode anti-lock braking is one of the things it was sold on, and it is also a system that goes quiet when it fails. Owner reports filed with the United States road safety agency across several model years describe two things that belong together: the warning lamp staying on, and wheels locking so that the truck skids instead of stopping straight. When the control unit sees something it does not trust, it lights the lamp and hands the brakes back to you unassisted — the truck still stops, but it stops the way a truck without anti-lock brakes stops, which is not how this one is set up to behave on a loose or wet surface. The usual reason is one wheel-speed signal rather than the control unit: these sensors sit where road water, brake dust and gear oil reach them, and on a truck of this age the harness that carries the signal has been flexing for decades. Before any of that, settle which lamp you are actually looking at, because the truck has two and they mean different things — the anti-lock lamp is the one this entry is about, and the separate brake warning lamp is the one that comes on for a low fluid level or the parking brake. That distinction is free to make and it decides whether the rest of this page applies to you at all. This entry is written from owner reports in aggregate rather than from a factory bulletin, so treat the ranking of causes as a starting order, not a diagnosis. Anti-lock braking is work that is critical to safety: if the codes point past a sensor, take it to a qualified mechanic with the factory procedure.

  BrakesSafety-critical

  • The anti-lock warning lamp stays on after the truck starts moving
  • Wheels lock and the truck skids in a hard stop instead of staying straight
  • No pulsing at the pedal in an emergency stop where there used to be some
  • The lamp only comes on after a few minutes of driving, then stays on

• Do not drive

  Brake accumulator has lost its charge

  The third generation's brakes are assisted by a hydraulic booster with a gas-charged accumulator bolted to it, and that accumulator is the single most reported fault on this truck. Mitsubishi recalled it for the first two model years this generation was sold in North America: the campaign says the accumulator may have been improperly manufactured, that it can leak its pressurised nitrogen over time, and that the result is an abnormal noise from the left of the dash panel plus a delayed first application of boost after the truck has been parked. Owners describe the noise the same way in every language — a chirp, a gobble, the honk of a goose — and the specialist supplier who sells the replacement names the same sound as the telltale. Two things this entry is careful about. The campaign covered vehicles built up to a cut-off date partway through its first year, and owner after owner reports the identical failure on a truck whose VIN is not on the list — including filings from later model years, each cited below and confirmed as a full-size Montero by its VIN. The entry therefore claims no factory authority outside the campaign's own years, and its tier reflects that. And the triage is not this site being cautious: one owner's mechanic told him not to drive it until it was repaired, another lost the brakes entirely at highway speed, and a third was told the truck could not be driven until the part was replaced.

  BrakesSafety-critical

  • A chirp, honk or gobbling noise from the left of the dash each time you use the brake
  • Brake and ABS warning lights together, often with a buzzer
  • The pedal travels much further than it used to, sometimes to the floor
  • The first stop after the truck has sat is unassisted, then normal assistance returns

• Do not drive

  Crankshaft pulley bolt loosens and the pulley departs

  This is the defining mechanical failure of the second-generation Montero and the one worth knowing before anything else on the engine. Mitsubishi's United States recall states that the bolt securing the crankshaft pulley can work loose and that the pulley can then fall off the vehicle, and it names the consequence in plain terms: loss of power steering assist, with an increased risk of a crash. The pulley is what drives every belt on the front of the engine, so when it leaves, the steering pump, the alternator and the water pump all stop at once — heavy steering, no charging and a rising temperature gauge, arriving together and without warning. Owner reports filed with the same agency are unusually numerous for this component and they add two things the campaign does not: some describe the bolt loosening again after it was tightened, and several describe the crankshaft nose itself being chewed out, which turns a fastener job into an engine. **Read the campaign's scope carefully, because it is narrower than the truck.** It names Monteros fitted with the smaller of the two petrol V6s, and the fitment above is set to that engine for exactly that reason — a truck with the larger V6 was never part of it. That boundary is not a statement that the larger engine is immune, and the cited owner reports are blunt about how it felt from outside: one asks why there is no recall for the bigger engine, another records being told their truck was excluded by its identification number. Owners of an excluded truck get the same inspection and none of the free repair. Treat a knock or a visible wobble at the front of the engine as this fault until it is proven otherwise, whichever engine you have, and do not drive the truck to find out.

  EngineSafety-critical

  • A knock or rattle from the front of the engine that changes with engine speed
  • The bottom pulley visibly wobbles or moves in and out while the engine idles
  • The steering suddenly goes heavy while driving
  • The charge warning lamp lights and the temperature gauge climbs at the same moment
  • The drive belts are thrown off the engine

• Do not drive

  Crankshaft pulley bolt works loose or breaks (V6)

  The single bolt through the middle of the crankshaft pulley backs out, then snaps. It is among the most-repeated complaints owners of the V6 first-generation Montero filed with the US federal safety regulator, and a repair database that names the engines affected puts the 3.0 V6 at the head of the list, and the reason it is filed here as a safety problem rather than an engine problem is what happens next: the pulley and every belt it drives leave the engine at once, so the power steering pump, the alternator and the water pump all stop together, without warning, at whatever speed the truck happens to be doing. Owners in the complaint records describe exactly that sequence, one of them ending in a loss of control. The repair is cheap while it is only a loose bolt and expensive once the crankshaft nose is chewed. Treat a knock from the front of the engine on this truck as this problem until you have proved it is not. This is safety-critical work: have it done by a qualified mechanic.

  EngineSafety-critical

  • A knock or heavy rattle from the very front of the engine, loudest at low speed
  • The crankshaft pulley visibly wobbles or rocks as the engine idles
  • The steering suddenly goes heavy while driving
  • The charge warning light comes on and the engine starts to heat up at the same time

• Do not drive

  Engine-bay fire on an ageing truck

  A handful of owners have reported engine-bay fires on these trucks to the US federal regulator — one while driving, two while parked. That is a small number, and it is why this entry is tiered as weakly as it is: nothing here establishes a design defect, and it should not be read as one. What it does establish is the failure mode worth taking seriously on any truck this old, where insulation has had decades to go hard, high-current connections have had decades to corrode, and something has almost certainly nested in the engine bay at least once. Several of the other problems documented for this generation end in leaked oil or fuel on hot metal. The right response to smoke or a burning smell is to stop, switch off, and disconnect the battery — not to drive on and see. Have a qualified mechanic go through the harness before you put it back on the road.

  Electrical systemSafety-critical

  • Smoke rising from under the hood, with or without a warning light
  • A sharp burning-plastic smell in the cabin or at the vents
  • A fuse blows again immediately every time it is replaced
  • Wiring insulation that has gone shiny, brown, sticky or melted where it touches metal

• Do not drive

  Front brake hose cracks and leaks

  Mitsubishi ran two separate United States recall campaigns on the front flexible brake hoses of this generation. The first says the wheel-side hose can crack when the steering is at full lock and the suspension at full travel — the two things that happen together every time the truck is manoeuvred hard or driven off pavement. The second, a much smaller campaign, covers cracking of the lower hoses. Either way the result is the same: fluid escapes from one front circuit, the pedal travels further than it should, and the truck stops on less than it was designed to stop on. These are the original rubber hoses on a truck that is now decades old, so age and heat have done their own work on top of whichever defect the campaign described. Both campaigns are United States ones filed with NHTSA; a truck imported from another market was never part of them, and nothing here says what any other market's authority required. Whatever the paperwork says, flexible brake hoses are a wear item with a service life, and on a truck this age they are inspected on their condition, not on their recall history.

  BrakesSafety-critical

  • The brake warning lamp comes on and stays on
  • The pedal sinks slowly while you hold steady pressure at a stop
  • The fluid reservoir keeps dropping without the pads being worn out
  • A wet, oily film on the inside of one front wheel or on the inner fender

• Do not drive

  Front brake line chafes through at the inner fender

  The rigid front brake lines pass through a hole in the inner fender. Mitsubishi's United States recall says that when a line is not centred in that hole it rubs on the edge, and the rubbing eventually opens pin holes in the wall of the line. The remedy the campaign describes is telling: a line still centred is simply bent back into place, and only a line already worn is replaced. That means the fault is progressive and silent for a long time — there is nothing to feel until the wall finally opens and pressure escapes. Owner reports filed with the same agency describe the same class of failure elsewhere on the run, with lines routed close enough to a neighbouring pipe to wear against it. On a truck of this age, corrosion works on the same lines from the outside, especially where they run behind a wheel that throws salt or coastal grit at them. A brake line that is leaking is not a defect you drive with, and finding the leak is not the same as knowing the rest of the run is sound.

  BrakesSafety-critical

  • The brake indicator lamp lights and does not go out
  • The pedal travels further than it used to before the truck slows
  • The fluid level falls with no wet wheel or wet caliper to explain it
  • A damp, dust-caked patch on the inner fender or along the frame rail

• Do not drive

  Front lower control arm weld may break

  Mitsubishi recalled late fourth-generation trucks because the right-hand front lower control arm could break at a weld joint made by a faulty welding process. The European alert cited below classes the risk as serious and states the failure mode plainly: the arm might break in normal use. It records the affected trucks as two model years; a separate Australian campaign covers the same defect, but no Australian record was reachable to cite, so this entry is scoped to the European record and owners elsewhere should run their own market's look-up. A lower control arm is what holds the bottom of the front wheel in place, so losing one is losing control of that corner — this is not a noise you drive to the shop with. The complication is that a worn bush or ball joint in the same arm makes almost exactly the same clunk, and the two demand very different urgency, so the first step here is the vehicle identification number and not the stethoscope. If the truck is in the affected build range and the recall has not been done, it should be recovered rather than driven. Suspension is safety-critical: have this inspected and repaired by a qualified mechanic.

  SuspensionSafety-critical

  • The vehicle identification number comes back as affected on the manufacturer's recall look-up
  • A clunk or knock from the right front over bumps and on turn-in
  • The steering wanders or feels vague and loose at speed
  • A visible crack, or a rust line, at one of the welds on the lower arm

• Do not drive

  Fuel leaks onto the ground with a full tank on a slope

  A factory safety recall, and one of the few faults on this truck that can start a fire without any warning light. The campaign describes it exactly: with the tank full and the vehicle parked facing forward on an upward slope, the fuel tank leveling valve may stop sealing if the fuel expands as the ambient temperature rises, and fuel can then leak onto the ground. The manufacturer's stated consequence is fire in the presence of an ignition source, and the remedy was to replace the valve. The pattern is what identifies it: no leak on level ground, no leak with half a tank, a puddle and a smell after the truck has sat nose-up in the sun on a full one. It is worth knowing that owners also report fuel leaking at the rear wheel well without that pattern, and one reports a leak that came back after the campaign repair — so a smell of fuel that does not fit the slope-and-full-tank picture still needs finding. Costa Rican driveways and parking spots are rarely level, which makes this a more likely find here than the campaign's home market would suggest.

  Fuel systemSafety-critical

  • A strong petrol smell after the truck has been parked nose-up
  • A wet patch or a puddle under the rear of the vehicle
  • It happens with a full tank and never with a half-empty one

• Do not drive

  Inner tie rod pulls out of its adjuster tube

  Among the steering complaints filed with the United States road safety agency for this generation there is one that stands apart from ordinary wear: an inner tie rod described as having pulled out of the threaded tube it screws into, with the driver losing steering control at the moment it let go. Reports name it in more than one model year. It is worth separating from the everyday worn joint because the failure mode is different. A worn ball joint gets loose, then vague, then noisy, and gives you months of warning. A rod that unscrews from its adjuster gives you the same vague steering for a while and then nothing at all, and the difference between the two is not something you can feel from the seat — it is something you find by putting your hands on the linkage. This truck's steering linkage is long, exposed and full of adjusters that are held by clamps, and every one of those clamps has spent decades in water and grit. Any new looseness, clonk or change in how the truck tracks is checked before it is driven, not after. If the linkage has play and you are not equipped to measure it, that is a tow, not a test drive.

  SteeringSafety-critical

  • The steering suddenly goes light and then does nothing at all
  • A clonk from the front of the truck when you turn the wheel or change direction
  • The wheel turns a noticeable amount before the truck starts to follow
  • One front tyre suddenly starts scrubbing its shoulder away

• Do not drive

  Oil pressure sending unit leaks onto a hot engine

  Mitsubishi recalled the analogue-gauge trucks of the model year this campaign is recorded against because the oil pressure gauge sending unit, on the right-hand side of the engine, could leak. The recall notice names both consequences: engine damage from the oil that is no longer in the engine, and an engine fire if that oil reaches hot metal. The remedy was a modified sending unit. Two things make this worth writing down four decades later. The first is that an oil leak on the right-hand side of one of these engines has a specific, cheap, known cause worth checking before anything else. The second is that an oil-fed engine-bay fire is exactly the kind of failure this site exists to warn about: if you can smell burning oil, stop and look, and do not keep driving. Have this checked by a qualified mechanic.

  EngineSafety-critical

  • Wet oil, or an oily crust, on the right-hand side of the engine block
  • A hot, sharp burnt-oil smell after a drive, strongest with the hood open
  • The dipstick keeps dropping but nothing obvious drips onto the ground overnight
  • The oil pressure gauge reads low, high or erratically compared with how it used to read

• Do not drive

  Seat belt buckle release button breaks up

  The red release button on the front seat belt buckles goes brittle, cracks, and drops pieces of itself into the buckle mechanism. Mitsubishi recalled it: the notice says in plain words that the belts would not protect an occupant in a crash. One owner complaint filed separately reports front and rear buckles failing together, which is the only cited evidence that the rear belts go the same way. This is a fault that does nothing at all until the moment it matters most, which is why the triage here is deliberately the strictest one: a seat whose belt will not latch and hold is a seat nobody should sit in, and a driver's belt that will not latch is a truck nobody should drive. A brittle button is also a good reason to look hard at the rest of a restraint that is decades old — webbing, anchor bolts, retractor. Restraints are safety-critical: have this work done by a qualified mechanic.

  Interior and trimSafety-critical

  • The red button marked for release is cracked, chalky or missing a corner
  • The metal tongue clicks in but pulls back out when you tug the belt
  • The belt latches but the button will not let it go without a fight
  • Something loose rattles inside the buckle when you shake it

• Do not drive

  Throttle does not close — the V6 icing recall

  Mitsubishi ran a safety recall on the V6 first-generation Montero because the throttle valve could ice up and stick, leaving the engine unable to drop back to idle. The remedy was a heated adapter plate under the throttle body. Owner complaints filed with the same regulator over the following years describe the outcome the recall was meant to prevent — a throttle that stayed open, a truck that surged from a stop, and in one case a rollover. The campaign record is listed against the first V6 model year only, while the owner complaints cited here come from the two later ones, so treat the model-year boundary as the paperwork's, not the fault's. Because the recall is decades old and these trucks have changed hands many times, a truck in front of you today may never have had the remedy fitted, and nobody can tell by looking. Anything that keeps the throttle from closing on its own is a safety-critical fault: do not drive the truck until it is fixed, and have the work done by a qualified mechanic.

  Fuel systemSafety-critical

  • You lift off the accelerator and the engine keeps revving instead of dropping to idle
  • The accelerator pedal feels held down or gritty, and does not spring back cleanly
  • The truck surges or creeps hard forward when you come to a stop
  • It happens on cold, damp mornings and not on warm dry days

• Do not drive

  Balance shaft belt takes the timing belt with it

  The 4D56 diesel runs two belts behind the same cover: the timing belt, and a smaller balance shaft belt sitting behind it. The inner belt drives nothing the engine needs to run, which is exactly why it gets forgotten — a truck can have had its timing belt changed on schedule for decades while nobody touched the belt underneath it. A buyer's guide written for this generation and an owners' club thread agree on what happens next, from different directions. The club's members describe a snapped balance belt taking the cam belt with it and describe the worn, chewed sections of tooth that mark where the shafts stopped turning. The guide states the outcome for a belt-driven diesel of this design in one sentence: a thrown timing belt usually means a replacement engine. **The fitment above is narrower than the guide's own sentence, deliberately.** That guide groups this generation's diesels together; this entry is scoped to the one engine the club thread is actually about and the one the belt pair belongs to. If your truck has the other diesel, do not assume the entry applies or that it does not — find out what drives your camshaft and your balance shafts before you plan a service around either answer. There is no warning light for this and nothing to feel from the seat. What you have instead is paperwork: if nobody can tell you when the inner belt was last changed, treat it as never. The same thread records that the club's own experienced members often remove the balance belt rather than replace it, and reports the engine running smoothly without it — that is a real and widely used answer, and it is also a change to how the engine was built, so it is set out below as its own choice rather than buried in the recommendation.

  EngineDamages other parts

  • No service record shows the inner belt was ever changed with the timing belt
  • A rattle or whine from behind the timing cover that changes with engine speed
  • A new vibration through the engine that was not there before
  • Oil pooled inside the timing cover and soaked into the belts
  • The engine stopped without warning and will not turn over properly or restart

• Do not drive

  Crankshaft pulley bolt letting go

  The Montero specialist who supplies the updated fastener describes the original crankshaft centre bolt as a defective design that would often back out and break, ruining the crankshaft and sometimes other engine components with it, and sells the replacement with thread locker already applied. Mitsubishi ran a factory campaign for the same fastener on the previous generation's smaller V6 and on another model. That campaign is not this engine and this entry does not claim it is — but it is worth reading, because the manufacturer's own stated consequence is a loss of power steering assist and an increased risk of a crash, and the manufacturer's own remedy was to tighten the bolt to the correct torque specification, replacing it only where it was damaged. This entry is scoped to the bolt already going: every symptom below — a pulley you can see wobbling, a knock from the nose of the crankshaft, a thrown accessory belt — is the failure in progress, which is why the triage is do not drive. A truck that simply still has the original bolt in it, with none of those signs, is a different situation: that is the factory campaign's own remedy, a torque check at the next service, not a reason to park it. **A warning about the popular shortcut.** Enthusiasts pass around a way to tell the two bolts apart by eye, from how far the head stands out of the pulley. The suppliers who sell the part do not describe it the same way round as each other, and this site could not reach a source good enough to settle which direction is correct — so it is not printed here. Identify the bolt by its part number instead. Getting that test backwards would tell an owner the defective bolt is the good one.

  EngineDamages other partsSafety-critical

  • A visible wobble or a knock at the crankshaft pulley with the engine running
  • The accessory drive belt thrown off or shredded
  • The battery warning light and heavy steering arriving together

• Do not drive

  Crankshaft pulley rubber perishes

  The crankshaft pulley on this engine is two metal rings bonded together through a rubber layer that damps torsional vibration. That rubber perishes with age rather than with distance, which is why the one source that documents this for the fourth generation says the failures turn up on trucks of a certain age regardless of how far they have gone. One source is why this entry carries the site's weakest confidence tier: the Spanish-language owner record beside it covers earlier trucks, and its single fourth-generation entry is somebody asking for a torque figure rather than reporting a failure — and every fourth-generation truck is now that age. When the bond lets go, the outer ring walks relative to the hub: the belt runs off line and squeals, then throws, and everything the belt drives stops. Spanish-language owner reports on the same family of trucks describe the related failure of the centre bolt working loose or breaking, which the first-generation entry on this site documents in detail from federal complaint records. Treat a wobbling pulley the same way in both cases: stop. Losing the belt takes the water pump and the steering assist with it, which is why this is filed as safety-critical work for a qualified mechanic rather than a noise to monitor.

  EngineDamages other partsSafety-critical

  • A belt squeal on a cold start that clears as things warm up
  • The pulley visibly wobbles or runs off line at idle
  • Black rubber crumbs collecting around the front of the engine or on the undertray
  • The drive belt has been thrown off or has shredded

• Do not drive

  Engine oil level rising — fuel in the sump

  An owner of an early fourth-generation diesel reported, after a long fight with particulate filter regeneration, that the sump had filled with a large quantity of diesel. That is one account, so this entry sits at the site's lowest confidence tier — but the mechanism behind it is not in dispute and is worth knowing before it happens to you. To burn the filter clean, the engine injects extra fuel late in the cycle; if the regeneration never completes, some of that fuel runs down the bores into the oil instead of burning. Diluted oil is thinner oil, and thinner oil does not protect bearings, so a filter problem quietly becomes an engine problem. This is why the triage here is stricter than the filter entry it follows from: an oil level that is rising on its own means the oil is no longer oil. Stop driving, check it cold, and get the cause found. Have this diagnosed by a qualified mechanic — and never keep driving a diesel whose oil level is climbing.

  EngineDamages other partsSafety-critical

  • The dipstick reads above full and nobody has topped it up
  • The oil on the dipstick smells strongly of diesel
  • The oil is thin, watery and black long before the next service is due
  • The particulate filter has been warning or regenerating repeatedly in the weeks before

• Do not drive

  Head gasket failure on the V6

  The cited overland thread follows one first-generation truck with the 3.0 V6 whose owner is working through a blown head gasket, with a cracked head raised as the thing that sometimes turns up beside it. That is a single truck in a single thread, so this entry sits at the site's weakest confidence tier: read it as a well-informed starting point, not as a statement about how often this engine does it. The reason to publish it anyway is the ordering below. A head gasket is expensive and a cooling system fault is cheap, and on a truck of this age the cooling system is very often what killed the gasket. Be careful how much weight you put on the thread here: the owner reports the radiator as being in good shape, and it is a member's suggestion — not a finding — that a radiator problem may have been one reason the gasket blew. That is a hypothesis worth testing cheaply, which is exactly what it is used for below. So the diagnostic steps here deliberately test both, and the cheap fix path exists on its own: if you replace a gasket without curing the reason it overheated, you will replace it again. Once coolant and combustion are mixing, keep driving and you turn a gasket job into a head job, or a block. That is why the triage is do-not-drive even though the engine will usually still start and move.

  EngineDamages other parts

  • The temperature climbs on a hill or towing and settles again when you back off
  • The coolant level keeps dropping and nothing drips on the ground
  • Persistent sweet-smelling white smoke from the exhaust once the engine is hot
  • A pale creamy deposit under the oil filler cap or on the dipstick

• Do not drive

  Rear axle shaft creeping out of the differential

  Australian-market owners describe this one in detail: a shaft works its way partway out of the rear differential, gear oil escapes past it, and the first sign is usually the smell and a stain rather than a noise. Mitsubishi Australia issued a field service notice rather than a recall — meaning the revised companion shafts, fitted with heavier retaining circlips, are supplied when a shaft actually fails rather than pre-emptively. One dealer in the thread had seen enough of them for the count to be worth quoting — it is in the citation — and a second owner in the same thread was one of that dealer's cases. The reported pattern is towing heavy loads, a lift, or both. A healthy shaft has a few millimetres of movement at the differential; a failing one moves in and out to the limit of the constant-velocity joints, and that difference is the test. Read the tier on this entry before you act on it: everything here comes from one forum thread, which is why it is filed as an owner account rather than as settled community knowledge. It is scoped as do-not-drive for the component rather than for the driver — nobody gets hurt, but a differential run without oil stops being a shaft-and-seal job and starts being a differential.

  DrivetrainDamages other parts

  • The distinct smell of gear oil, and a stain around the shaft where it enters the differential
  • Oil thrown along the back of the vehicle, or onto whatever is being towed
  • The shaft slides in and out at the differential instead of holding still
  • It appeared on a trip with a heavy load behind, or on a lifted truck

• Do not drive

  Rear heater tee pipes dump the coolant

  The trucks fitted with the rear heater carry the coolant a long way back and return it through plastic tee joints in the middle of the vehicle. The specialist supplier's standing advice is to replace those tees preventively whenever the cooling system is already drained, and their reasoning is the whole entry: if one of the old plastic pipes breaks, all of the vehicle's coolant drains out, which can overheat the engine and turn a cheap plastic fitting into cylinder head work. That is why this sits at do-not-drive. Nobody is hurt by it, but the distance between the puddle and a warped head is measured in minutes of running, and the temperature gauge on a system that has already emptied itself does not necessarily rise in time to be useful. If your Montero has rear heating and you are already draining the system for something else, this is the cheapest insurance on the truck. This entry rests on one specialist supplier's standing recommendation, so it is filed at the weakest tier — the consequence it describes is severe, and it is still one source.

  CoolingDamages other parts

  • A large puddle of coolant under the middle of the vehicle rather than under the nose
  • The temperature gauge climbing with no other warning
  • The level in the reservoir keeps falling and nothing is wet at the front
  • A sweet smell and steam from underneath after a run

• Do not drive

  Runs hot in traffic or on a long climb

  A buyer's guide written for this exact generation puts the cooling system on its inspection list and says why in one line: old radiators, old hoses and tired viscous fans cause overheating, and on the diesels the bill that arrives afterwards is a cracked or warped cylinder head. That is the whole reason this entry carries the severity it does. Overheating is not itself an expensive fault — a radiator, a fan coupling and a thermostat are ordinary parts. What is expensive is the head that was cooked while somebody drove another few kilometres hoping the gauge would come down. It does not come down, and the damage is done in that few kilometres rather than over the following month. The pattern of when the gauge rises is most of the diagnosis and it costs nothing to observe: hot only in traffic and at low speed points at airflow, which means the fan; hot only when working hard on the open road points at the radiator's ability to shed heat; hot everywhere and quickly points at circulation. Stop, let it cool, and do not open a hot system — the coolant in there is above its boiling point and held down only by the cap.

  CoolingDamages other parts

  • The temperature gauge climbs in traffic or on a long climb and falls again when you get moving
  • Normal on the open road, high whenever the truck is worked or slowed
  • The coolant level keeps falling with nothing on the ground
  • The heater blows cold at exactly the moment the gauge reads high
  • A sweet smell and steam from the front of the truck

• Do not drive

  Variable intake butterfly valves rattling on the 3.8

  This one belongs to the larger petrol V6 fitted to the later trucks, and the specialist supplier states the mileage at which it starts — the figure is in the citation below rather than in this paragraph, so it is written down once. The failure is mechanical: the butterfly rod bushings wear, the rod leaks air, and the screws, bushings and butterfly valves in the surge tank can end up in the combustion chambers. Enthusiasts have a nickname for it that tells you the stakes better than any severity rating. This entry is deliberately scoped to a truck that is already telling you something — a rattle, an unsteady idle, rough running — rather than to mileage alone; high mileage on its own is a reason to inspect, not a reason to stop driving. Once it does rattle, the hardware is loose upstream of open valves, and that is the point at which the truck should stay parked. The choices are to rebuild the assembly, to remove it entirely and blank the rod port, or to buy a replacement surge tank, and the supplier is honest that deleting it costs a noticeable amount of torque.

  EngineDamages other parts

  • A rattle from the top of the engine at idle that changes with throttle
  • An unsteady idle that behaves like a vacuum leak
  • Rough running that survives plugs, coils and a fuel service

• Drive gently — repair soon

  Driver airbag inflator recall on late trucks

  Mitsubishi Motors North America recalled the driver airbag inflators fitted to the last United States trucks of this generation. The campaign says the inflators can absorb moisture over time and then either rupture when the airbag fires, sending metal fragments at whoever is behind the wheel, or underinflate so that the airbag does not do its job at all. Both outcomes only appear in a crash, which is what makes this different from every other fault on this site: nothing about how you drive changes the risk on any single trip, and there is no test you can run in the driveway. What does change is exposure — the defect is a moisture problem that accumulates, and every additional month of humidity and heat is on the wrong side of it. That is the honest reason the triage here is not simply 'drive normally': keep using the truck if you must, but get the remedy booked rather than filed away. The remedy is a free inflator replacement at a dealer, and this generation is old enough that a truck may have changed hands several times without the notice ever reaching the current owner. Never open, probe or attempt to replace an airbag module yourself. The campaign is a United States one; a truck sold or imported elsewhere was not part of it, and what any other market required is not stated here.

  Interior and trimSafety-critical

  • Nothing in the truck's history shows the inflator campaign was ever carried out
  • The airbag warning lamp no longer behaves the way it used to at start-up
  • The centre pad of the steering wheel looks swollen, lifted or distorted
  • The horn in the steering wheel pad works only sometimes

• Drive gently — repair soon

  Play in a front ball joint

  The third generation runs independent front suspension with an upper and a lower ball joint per side, and both are wear items on a truck this heavy. A worn joint announces itself as a clunk turning into a driveway and a truck that wanders enough that you are always correcting it; a torn boot that let the grease out is what usually got it there. The supplier who stocks the genuine parts is explicit that on trucks carrying larger tires or working off-road, factory joints are the only ones they will recommend — a joint is not the place to find out an aftermarket part was optimistic. The triage here is deliberately drive-gently-repair-soon and not do-not-drive, because a joint with detectable play is not the same thing as a joint about to separate. If the play is gross, or the boot is gone and the joint is dry and notchy, stop driving it and get it looked at.

  SuspensionSafety-critical

  • A clunk from one front corner turning slowly, as into a driveway
  • The truck wanders on the road and needs constant small corrections
  • One front tire wearing unevenly across its width
  • A split or missing rubber boot at the joint, with grease thrown around it

• Drive gently — repair soon

  Takata airbag inflator recall

  Fourth-generation trucks across several markets were recalled because the airbag inflator's propellant degrades with heat and humidity, and a degraded inflator can burst its metal housing instead of inflating the bag, firing fragments at the people it is meant to protect. The Australian and European regulator records cited below say so in those words. This is a fault with no symptom: nothing about the truck changes, nothing lights up, and the fault only exists at the one moment you would want the airbag to work. Only one of the cited records classifies the inflator by type — the Beta passenger inflator, on the 2013 to 2017 trucks — so do not read a type off this page for the earlier ones. The only diagnosis is to check the vehicle identification number with the manufacturer and to get the completion record if somebody tells you it has been done. Costa Rica is a hot, humid market, which is the exact combination the recalls name as the accelerator. The replacement is free under the recall in the markets that issued it, and a free repair with no expiry is not a repair to defer. Restraints are safety-critical: this is dealer work, not driveway work — never attempt to remove or handle an undeployed inflator yourself.

  Interior and trimSafety-critical

  • The vehicle identification number comes back as affected on the manufacturer's recall look-up
  • Nothing at all — the truck gives no sign that the inflator has degraded
  • The airbag warning lamp stays lit, which is a different fault worth chasing separately

• Drive gently — repair soon

  Trailer hitch receiver weld cracks

  A bolt-on trailer hitch sold for this truck was recalled because the weld holding the receiver tube could break, letting a trailer separate from the vehicle without warning. The recall was raised by the hitch maker, not by Mitsubishi, so it is filed under the vehicle in the federal database rather than in any Mitsubishi service literature — which is precisely why an owner is unlikely ever to hear about it. The brand and part number of the recalled hitch are recorded in the source cited below. Two things follow. If your truck wears that hitch, it should not tow anything until it has been replaced. And on any thirty-five-year-old truck, whatever the brand, the hitch welds are worth a wire brush and five minutes before the first trip of the season. The truck itself is fine to drive; it is towing that is the hazard here. Towing equipment is safety-critical: have a qualified mechanic inspect and replace it.

  BodySafety-critical

  • A hairline crack running along the weld where the receiver tube meets the crossbar
  • A rust stain weeping out of one weld line while the rest of the hitch looks sound
  • The receiver tube shifts or springs when you lever it by hand
  • A knock or groan from the hitch under load that was not there before

• Drive gently — repair soon

  Automatic slipping, flaring or refusing to shift

  A buyer's guide for this generation puts the automatic's problem down to heat: towing, old fluid, a clogged cooler and high temperatures shorten its life, and the guide tells a buyer to look for smooth shifts and clean fluid as the test. Owner reports filed with the United States road safety agency add the specific complaints that show up first — a transmission that will not shift properly when the truck is cold, and torque converters that failed. Heat is the whole story here and it explains why the symptoms arrive in the order they do. Transmission fluid does not wear out gradually and evenly; it survives until it has been cooked, and then it stops doing the two jobs it has, which are carrying pressure and holding friction. Once the fluid has gone, what it destroys is the clutch material inside, and that is the part that turns a fluid service into a rebuild. So the useful judgement is not about the transmission — it is about time. A truck that is slipping today can often be saved with a service; the same truck a thousand kilometres later usually cannot. Drive it gently, keep it off towing and long climbs, and get the fluid looked at this week rather than at the next service.

  TransmissionDamages other parts

  • It will not shift properly until the truck has warmed up
  • The engine revs rise between gears, and the truck does not gather speed with them
  • A shudder or a fine vibration at a steady cruise that goes away when you touch the throttle
  • The fluid on the dipstick is dark brown and smells burnt
  • A harsh bang into gear where it used to be smooth

• Drive gently — repair soon

  Diesel particulate filter will not regenerate

  The filter fills with soot, the warning lamp comes on, the engine tries to burn the soot off and cannot, and eventually the engine management lamp joins in and the power goes. Owners in the cited club threads single out the earliest automatic fourth-generation diesels as the ones that give the most trouble, and report that dealer forced regenerations on those trucks can fail repeatedly. Two of their findings are worth carrying into any diagnosis. First, a blocked filter is detected by a pressure difference across it, so a fault in that sensing circuit produces the same warning as a genuinely blocked filter — one member found the filter almost clean after all the warnings said otherwise. Second, soot burns and ash does not: a filter full of ash will not respond to any amount of regeneration, forced or otherwise, and needs cleaning or replacing. The reason the triage is not simply drive-normally is what happens next when regeneration keeps failing — see the engine-oil level entry for this generation.

  ExhaustDamages other parts

  • The particulate filter warning lamp is lit, or flashing
  • The engine management lamp joins the filter lamp
  • The truck loses power, especially pulling a hill or loaded
  • Fuel consumption gets far worse for a stretch of driving and then recovers

• Drive gently — repair soon

  Front axle will not release and the driveline binds

  This is the expensive half of the same vacuum-actuated front axle. When the clutch stays engaged after you have asked for two-wheel drive, the front and rear axles are tied together on a surface with grip, and on dry pavement they cannot both be right about how far the truck has travelled through a corner. Something has to give up the difference, and on this truck that something is a tyre chirping, the steering fighting back, and the driveline winding up until it releases with a bang. Do that repeatedly and the wear lands in the transfer case and the front axle, which is why this entry is marked as damaging and its twin — the axle that never engages at all — is not. There is one thing to check before assuming a fault, and it costs nothing. Super Select is designed to be used with the centre differential open on pavement, and if the truck has been left in a locked mode it will bind exactly like this while behaving completely correctly. Get out of the locked mode, drive in a straight line on a loose surface to unwind what is stored in the driveline, and see whether the complaint is still there. If it is, it is the control side or the actuator, and the supplier's own note about matching the hose routing when a solenoid is replaced is worth heeding: crossed hoses turn 'will not engage' into 'will not release'.

  Transfer caseDamages other parts

  • The truck binds and hops through tight turns on dry pavement
  • The steering fights back and the truck resists turning when parking
  • The front-wheel indicator keeps blinking after two-wheel drive is selected
  • A shudder and a groan from the front on full lock
  • The front tyres scrub and wear far faster than the rears

• Drive gently — repair soon

  Gear oil weeping from a differential seal

  Both differentials on this truck use seals at the pinion nose and where the shafts leave the housing, and the specialist supplier lists four separate part numbers to cover those positions — which is a fair map of where the oil comes out. The failure is slow and quiet, which is exactly the danger: the level falls over months and there is no gauge, no warning light and no noise until the gears have already been running short. A forum thread about the same axle notes that the distinctive smell of gear oil is usually what tells an owner first, before any stain is obvious. One cause worth checking before you condemn a seal is the housing breather. If it is blocked, the housing pressurises as it heats and pushes oil past seals that were doing their job perfectly well, and clearing it costs nothing.

  DrivetrainDamages other parts

  • An oily film around the pinion nose or the side of a differential housing
  • Oil flung along the underside or onto the inner face of a wheel
  • The oil level is below the filler plug when you check it
  • A whine that rises and falls with road speed rather than with engine speed

• Drive gently — repair soon

  Harsh or hesitant shifts, and the fluid nobody can name

  The most avoidable transmission failure on this truck is a fluid decision. The specialist supplier who assembles the service kit says it in one sentence: they have seen several of these transmissions ruined by shops using the wrong fluid, which is why their kit ships with the manufacturer's own fluid and a printed copy of the factory procedure. An owner complaint filed against this generation describes grinding from the transmission on a truck whose owner had every required service done, with a quote in the thousands, so the downside is real. The practical consequence is an order of operations: the first question is which fluid went in last, by name, not what the symptom is. The specification is on the parts list below rather than in this paragraph, so there is one place to read it and one place to get it wrong.

  TransmissionDamages other parts

  • Shifts that thump, flare or hesitate where they used to be smooth
  • A shudder under load or on a long climb
  • Fluid that is dark on a rag or smells burnt
  • No record of the transmission ever having been serviced

• Drive gently — repair soon

  Oil leak at the front camshaft seals

  The kit supplier for this engine names the front camshaft seals as a common oil leak point and recommends replacing them on a fixed cadence rather than waiting for them to weep — and the reason is not the oil you lose. These seals sit behind the timing covers, which means the oil they leak lands on the timing belt, and a belt that has been soaked in oil is a belt on borrowed time regardless of how new it is. The economics follow from the geometry: the labour to reach the seals is the labour of a timing belt service, so a seal replaced during that job is nearly free and a seal replaced on its own is not. If the front of your engine is wet and the belt history is unknown, read this entry and the timing belt one together — they are the same afternoon of work. This entry rests on one specialist supplier's product documentation, so it is filed at the weakest tier — the reasoning below is sound, but nobody has corroborated it here yet.

  EngineDamages other parts

  • Oil weeping from the area of the timing covers
  • The oil level falls but nothing pools on the ground
  • A burnt oil smell after a run, strongest with the hood up
  • Black rubber dust in and around the front cover

• Drive gently — repair soon

  Structural corrosion at arches, sills, body mounts and frame

  A buyer's guide written for this generation puts corrosion at the head of its inspection list and says exactly where to look: rear arches, sills, body mounts and the frame itself, with the frame rails, the rear crossmember and the floor pans called out as inspection points. It adds the sentence that matters most to anyone deciding what to do about it — repairs quickly exceed what the truck saves you. That guide is the only source here for the frame and body-mount half; the owner reports cited alongside it establish something narrower and worth having anyway, which is that owners of these trucks have taken corrosion severe enough to need parts replaced to a national regulator, in their case at the rear door hinges. Read that as evidence these bodies rot, not as evidence about any particular frame. This is a body-on-frame truck, so the rust question splits in two and the two halves are not equally serious. Corroded arches and sills are metal and money. Corroded body mounts and a corroded frame are structure: they are what holds the cab to the chassis and the suspension to the truck, and there is no cosmetic version of that. That split is why this entry carries the safety framing even though its severity is written as damaging — the fault destroys the truck slowly, but it destroys a part of the truck whose failure is not slow. The other reason to look properly is that corrosion is the one fault that gets deliberately hidden. Fresh underseal on a truck of this age is a question, not an answer, and the honest test is still a light tap: sound metal rings, tired metal thuds.

  BodyDamages other partsSafety-critical

  • Paint bubbling or lifting along the rear wheel arches
  • Flaking scale along the sills below the doors
  • Rust blooming around a body mount where the cab meets the frame
  • A dull thud instead of a ring when the panel is tapped
  • Fresh, thick underseal covering an otherwise unrestored underside

• Drive gently — repair soon

  Timing belt service overdue or unknown

  The Montero specialist who assembles the OEM kit for this generation states it plainly: these are timing-belt-driven interference engines on a fixed service interval, and after collision damage the most common reason they see a Montero reach a scrapyard is a blown engine from a timing failure. That makes an unknown belt history a real problem rather than a paperwork gap — on an interference engine the belt does not strand you, it ends the engine. The same source warns that cheap aftermarket kit parts fail early, and lists what should always be replaced together: the belt, the tensioner and its pulley, the idler pulley, and the water pump with its gaskets. If you have just bought a Gen 3 and there is no receipt for this job, treat it as due. On a truck that lives at the end of a bad road, the arithmetic is not close. The interval and the interference-engine claim both come from one specialist supplier's kit documentation, so this entry is filed at the weakest tier. Treat the recommendation as sound trade practice rather than as a factory specification, and confirm the interval for your own market's service schedule.

  EngineDamages other parts

  • Nobody can say when the timing belt was last replaced
  • A rattle or squeal from behind the front cover at idle
  • Coolant weeping from the area of the timing cover
  • The engine spins freely and will not start after a bang or a sudden stop

• Drive gently — repair soon

  Turbocharger vanes stick, or the turbo fails

  The fourth-generation diesel uses a variable-vane turbocharger, and the vanes that make it flexible are also what soot sticks to. The cited source names the causes as oil-related — long oil change intervals, the wrong oil specification, and not letting the engine warm up or cool down — and separates two outcomes: a vane mechanism that has gummed up, which can sometimes be cleaned if it is caught early, and a turbocharger whose bearings have failed, which cannot. This is a single source, so the tier is the site's weakest, but the ordering it implies is sound and cheap to follow. Before either of those, eliminate a boost leak: a split intercooler hose or a loose clamp gives the same flat, smoky, comes-and-goes performance for the price of a clamp. If the turbo is passing oil, it is feeding the intake, and continuing to drive it hard risks the engine running on its own oil — which is why this is not filed as drive-normally.

  EngineDamages other parts

  • Heavy black smoke under load
  • Blue or white smoke at idle or on start-up
  • A whine, siren or rattle from the turbocharger that rises with engine speed
  • The truck pulls strongly sometimes and flat at others, with no pattern you can pin down

• Drive gently — repair soon

  Free-wheeling hub will not drive the front wheel

  You select four-wheel drive, the transfer case goes in, and one front wheel still does nothing. This rests on a single club thread rather than the several independent ones a stronger tier would need, so treat it as a well-argued starting point. On the automatic hubs, the answer in that thread is a small driving dog inside the hub that has snapped off — and the loading that snaps it is exactly the loading you apply when you are already stuck and rocking the truck forward and back. Members describe a ratcheting sound from the hub as the warning that comes first, which makes it worth acting on rather than driving through. The same thread is unanimous that the factory manual hubs are the stronger part and bolt straight up in place of the automatics, which is why that is listed here as a fix and not as a modification. The truck drives perfectly well in two-wheel drive with a dead hub, so this is not an emergency on tarmac — it is an emergency the first time you need the front axle and do not have it.

  Transfer caseCan strand you

  • A ratcheting or clicking noise from one front wheel, often only when turning
  • Four-wheel drive is selected and engaged but the front wheels are not pulling
  • One front wheel clearly drives and the other one spins free
  • The dial on a manual hub will not turn to the locked position

• Drive gently — repair soon

  Injection pump seal leaks and cold starting gets worse

  A long-running Spanish-language owners' forum thread devoted to this engine's injection pump describes it as a defect the engine simply has, with one experienced member writing that they all come to it sooner or later, and warning that a truck left with the worn seal will fail to start cold and will get worse each time. A buyer's guide for this generation names the same thing more briefly, listing injection pump seal leaks among the fuel-system items to expect and attributing them to ageing seals. The two agree on the shape of it: this is a wear item on a mechanically injected diesel, not a design catastrophe, and the seal itself is a cheap part. What makes it worth its own entry is the gap between that part and the bill. The forum thread's whole point is the gap between the two: the seal itself sits at the very bottom of the cost band, and the quote the poster was given for the same job sat at the top of it, because getting to the seal means the pump comes off and goes back on, and a distributor pump that goes back on wrong does not run. The fix path below carries the whole span as a band rather than a figure, which is the only honest way to state a price that depends on your market, your currency and your year — where you land inside it is decided by who does the work, not by the part. The cold-start-only pattern is what points here rather than at the glow plugs, which fail with the same complaint and are far easier to check first. Diesel around a hot engine is a fire risk: if you can see fuel dripping rather than a damp film, that is a different and more urgent problem and the truck stops until it is fixed.

  Fuel systemCan strand youSafety-critical

  • It starts harder from cold every few weeks, on a curve that only goes one way
  • Starts on the button when warm and fights you every cold morning
  • A damp, dust-caked film of diesel around the pump and down the block below it
  • Long cranking before it catches, sometimes with a puff of white smoke
  • Rough, uneven running for the first minute and then normal

• Drive gently — repair soon

  Shakes at idle and stalls at a stop

  A recognisable cluster in the owner-complaint record for this generation: the engine vibrates at a standstill, the tachometer needle sinks towards zero as though the engine is about to die, and it either catches itself or stalls and restarts without drama. The useful part of those filings is what happened next. One owner had the dealer change plugs and cables and was told to use premium fuel; the vibration was back within a week. Another had the idle speed control replaced after repeated stalling and kept filing. Nobody in the cited set reports the fault being cured on the first attempt — which says the symptom has more than one cause, and that parts-swapping in the dark is expensive. The triage is drive-gently-repair-soon rather than drive-normally for one reason: an engine that stalls unpredictably will eventually do it pulling into traffic. Get the codes read before anybody sells you an ignition service.

  EngineCan strand you

  • The engine shakes at idle and feels as if it is about to die
  • The tachometer needle sinks towards zero and then recovers
  • It stalls at a stop and then restarts normally
  • The check engine light comes on, often with a misfire code stored

• Drive gently — repair soon

  Amber centre-diff light blinking, transfer case will not change mode

  Five switches sit on top of the transfer case and tell the truck which mode the selector is actually in. When one stops answering, the amber centre-diff-lock symbol on the dash blinks, and depending on which switch it is the selector will refuse to leave the mode it is in. The pattern owners report most often is a light that starts blinking after a set distance of highway driving, goes out when the engine is restarted, and comes back after the same distance again. The specialist supplier's advice is to pull the transfer-case-specific trouble code first and confirm with a resistance measurement on each switch rather than replacing all five, and to clean the detent ball and its cavity and fit a new crush washer whenever a switch comes out. In the Spanish-language thread a third-generation owner's fault turned out to be a low transfer case oil level, while others in the same thread cleaned the switch connectors instead — which is exactly why the code comes before the parts.

  Transfer caseWorks worse

  • The amber centre-diff-lock symbol on the dash blinks on its own
  • The selector refuses to move out of the mode it is in
  • Restarting the engine clears it, and the same distance of driving brings it back
  • A clunk from underneath as the drive tries to engage and lets go again

• Drive gently — repair soon

  Brake judder through the pedal and the steering wheel

  Owner reports filed with the United States road safety agency return to this one across the later model years of the generation — the fitment above is set to the years those reports actually cover, not to the whole run: the pedal pulses, the steering wheel shakes when the brakes come on, the front discs get machined, and the judder is back well before the next set of pads is due. The repeat is the useful part of the story. A disc that is machined and then judders again was rarely the whole fault — something is still making one part of the disc face run hotter, or thicker, than the rest. This is a heavy truck on a front disc that was sized for a heavy truck, and the two usual culprits are a caliper that no longer slides freely and a wheel that was hammered on with an impact gun instead of torqued in sequence. It is uncomfortable rather than dangerous on its own: the brakes still work, and they still work well enough to stop the truck. What earns the caution is what tends to be underneath it — a caliper that drags is also cooking the fluid and the pads on that corner, and a bearing loose enough to show as judder is a different problem wearing a brake costume. Drive it gently, avoid long descents on the brakes, and get it looked at.

  BrakesWorks worseSafety-critical

  • The pedal pushes back in a rhythm while you brake
  • The steering wheel shakes side to side only when the brakes are applied
  • The judder comes back not long after the discs were machined
  • One front wheel is far hotter than the other after an ordinary drive

• Drive gently — repair soon

  Cracked exhaust manifold

  The specialist supplier who imports replacements for the 3.5-litre V6 describes cracked original manifolds as very common, and the shape of their catalogue tells the same story: they stock left and right castings, they warn that a junkyard unit has a high probability of being cracked too, and they list all three gaskets the job consumes. The symptom this entry leads with — a tick from the engine bay on a cold start that fades as the metal expands and the crack closes up — is not in that source; it is the ordinary mechanical reading of a cracked casting, and it is set down here as inference so a reader can weigh it as such. It is worth knowing because it is exactly why the noise is so often mistaken for a valvetrain problem and chased in the wrong place. This entry is scoped to the years the cited source covers; the later 3.8-litre trucks take different castings and are not claimed here. Two things to be careful about. An exhaust leak upstream of the oxygen sensor changes what the engine management sees, so a fuel-trim or sensor code here may be a symptom rather than a fault of its own. And any exhaust leak is a reason to keep the cabin ventilated until it is fixed; if you smell exhaust inside the vehicle, that is a different and more urgent problem than this one. Everything here comes from one specialist supplier's product documentation, which is why the entry is filed at the weakest tier: it is a trade opinion, not an aggregate of owners agreeing.

  ExhaustWorks worse

  • A sharp tick from the engine bay on a cold start
  • The tick fades or disappears once the engine is warm
  • The smell of exhaust around the engine bay with the hood up
  • A check engine light for an oxygen sensor or fuel trim reading

• Drive gently — repair soon

  Front brake discs wear out fast

  One owner told the federal regulator they had replaced the front discs five times in four years, ending each time in metal-to-metal grinding and a pedal that needed far more effort than it should. That is a single report and this entry is tiered at the bottom of the site's scale to say so. It is published because the pattern it describes — new front brakes that do not last — almost never means the parts were bad, and almost always means something is holding the pads against the disc after you take your foot off. The four causes below are the usual suspects, in the order that costs least to eliminate. One extra warning from a second complaint in the same records: check the length and run of the flexible hoses whenever the truck goes up on a hoist, because a hose pulled tight as the suspension hangs is a hose being damaged. Brakes are safety-critical. Grinding brakes still stop the truck, but with less margin than you think and no margin at all when they are hot: keep speeds down, leave more room, and get this to a qualified mechanic rather than putting it off.

  BrakesWorks worseSafety-critical

  • A harsh metallic grinding from the front when you brake
  • The brake pedal travels further before the truck slows
  • The front discs are worn thin again far too soon after the last set
  • One front wheel is much hotter than the other after a normal drive

• Drive gently — repair soon

  Green front-wheel symbols blinking, front axle will not engage

  This is the other blinking-light fault, and it is not the same one as the transfer case switches. When the green front-wheel symbols blink rather than the amber centre-diff symbol, the front axle is having trouble engaging or disengaging, and the part the specialist supplier names as the usual culprit is the freewheel clutch control solenoid — a vacuum valve that is easy to reach and quick to change, and one they recommend carrying spare. Around it are the vacuum hoses on the right inner fender and the clutch actuator diaphragm on the front differential itself, and Spanish-language owner threads describe both: a solenoid valve that fixed it outright, and a differential clutch actuator diaphragm replaced alongside it. Owners also report the clutch sticking on trucks whose four-wheel drive is never used, which is an argument for exercising it rather than a fault to buy parts for.

  Transfer caseWorks worse

  • The green front-wheel symbols on the dash blink instead of holding steady
  • Selecting four-wheel drive does nothing at the front axle
  • The front drive will not release once it has engaged
  • The steering binds and the tires scrub in tight turns on dry pavement

• Drive gently — repair soon

  Injector and high-pressure pump wear at high mileage

  The fourth-generation diesel uses a high-pressure pump feeding a common rail and electronic injectors, which is a different system from the earlier trucks and wears differently. The cited source describes what high-mileage wear looks like: harder cold starting, a slight misfire at idle, fuel consumption creeping up, and eventually smoke under load. It calls this normal wear on precision components rather than a defect, and this entry follows it at the site's weakest confidence tier because it is a single source. The practical point is the order of elimination. Injectors and pumps are the expensive answer and the fashionable diagnosis, and three cheaper things produce the same symptoms — a tired fuel filter, water or dirt in the fuel, and failing glow plugs. Work through those first. Fuel systems are safety-critical: high-pressure diesel injection is not a system to open casually, so have the testing and any repair done by a qualified diesel specialist.

  Fuel systemWorks worseSafety-critical

  • The engine takes noticeably longer to start when cold
  • A slight misfire or shake at idle that was not there before
  • Fuel consumption creeping up over months with no change in how the truck is used
  • Smoke from the exhaust under load

• Drive gently — repair soon

  Knock and creak from the top of the front strut

  The mount at the top of each front strut carries the whole corner and lets the strut rotate with the steering, and it is the noise nobody attributes correctly. Because it lives under the hood rather than under the truck, a knock from here reads to most people as a suspension problem down at the wheel, and the parts that get replaced first are usually the wrong ones. The supplier who stocks the replacement is realistic about it: the factory metal top hats can usually be reused when other strut components are changed, and it is the rusty or broken ones that need replacing. That is the whole diagnosis in one sentence, and it takes opening the hood to make. In a wet climate with salt-free but constantly damp air, corrosion at the strut top is worth a look every time the hood is up for anything else.

  SuspensionWorks worseSafety-critical

  • A knock that seems to come from up under the hood rather than down at the wheel
  • A creak or groan when the steering is turned at a standstill
  • Visible rust or a cracked mount at the strut top with the hood open
  • The steering feels notchy or sticky at parking speed

• Drive gently — repair soon

  Knock from the front end over small bumps

  The links that tie the front sway bar to the suspension are short, they carry every roll input the bar generates, and they are among the first things on this truck to start knocking. The knock is loudest over small, sharp bumps and quietest on smooth road, which is what separates it from a worn bushing further inboard. The left and right links are different parts, so replacing one means ordering the correct side, and the supplier who stocks the genuine ones warns specifically that on trucks running larger tires the aftermarket links do not hold up to the extra load — worth knowing before you buy the cheap pair twice. This entry is scoped to a link that is worn and knocking. A link that has actually come apart changes how the truck behaves in an avoidance manoeuvre, and that is not a drive-gently situation.

  SuspensionWorks worseSafety-critical

  • A knock or clunk from the front end over small bumps
  • The noise is loud on broken surfaces and disappears on smooth road
  • The truck leans more in corners than it used to
  • You can move the link by hand and feel the play in it

• Drive gently — repair soon

  Loose, wandering steering with a dead spot

  Steering that has gone vague is the most ordinary complaint on a truck of this age and the easiest one to live with until it is not. Owner reports filed with the United States road safety agency across this generation describe the whole range of it: a truck that drifts and needs constant small corrections, a wheel with a dead area either side of straight ahead, and in one report a column with enough front-to-back movement to be measured in inches. This truck steers through a recirculating-ball box, a pitman arm, a long relay rod and an idler arm on the other side, and every one of those is a wear point in series with the others. That is why the fault creeps: no single joint is badly worn, but five slightly worn joints add up into a wheel that does nothing for the first part of its travel. The reason to treat it as more than an annoyance is that free play hides the joint that is actually failing — a linkage with a lot of slop everywhere is a linkage where nobody can tell which part is nearly out. This entry is written from owner reports in aggregate; the ranking of causes is a starting order, not a diagnosis for your truck.

  SteeringWorks worseSafety-critical

  • The wheel moves through a dead area either side of straight ahead before anything happens
  • The truck wanders in its lane and needs constant small corrections
  • The column itself moves in and out or up and down when pulled
  • Steering feel that got vaguer so slowly nobody noticed a day it changed

• Drive gently — repair soon

  Shimmy and vibration at highway speed

  This is the single most-reported chassis complaint filed with the United States road safety agency for the later trucks of this generation. Owners describe a steering wheel that has to be held with both hands, shaking that arrives in a narrow band of road speed, and — the part that matters for diagnosis — a fault that survived new tyres, repeated balancing and more than one visit to a workshop. One owner report goes further and names the front upper control arm joints and their bearings as what was eventually found — one report, not a pattern, and the causes below are ranked on how this failure usually goes rather than on that single account. The pattern worth trusting is the broader one: many owners, several model years, one complaint that survived the obvious fixes. When a vibration comes back after the wheels have been balanced twice, the wheels are usually not the story: something in the front end has enough freedom to let the wheel steer itself a little, and the tyre then feeds that movement back through the linkage. This is a heavy independent front end with torsion bars, and every joint in it is decades old. It is not dangerous the way a separated joint is dangerous, and the truck stays perfectly controllable at ordinary speeds — but shimmy is a symptom of looseness, and looseness in a front end is on a path that ends somewhere worse. Keep the speed down and get the joints measured.

  SuspensionWorks worseSafety-critical

  • The steering wheel shakes side to side once the truck is up at highway speed
  • The vibration appears in a band of speed and eases off above and below it
  • Shaking felt through the seat and the floor as well as the wheel
  • It is still there after new tyres and after the wheels were balanced again

• Drive gently — repair soon

  Steering goes heavy and will not self-centre

  One owner described the mechanism to the federal regulator clearly enough to be worth recording: road grime and salt pit the shaft where it enters the steering gear, the rough shaft tears the seal, the lubrication leaves, and the truck becomes hard to steer and will not return to straight on its own without being helped round. That is a single report, which is why this entry carries the weakest confidence tier on the site — read it as one plausible explanation among several, not as an established pattern. The reason it earns a page anyway is that the symptom is common on trucks of this age and the four causes below are cheap to tell apart in the order given, starting with the fluid. Steering is safety-critical. Heavy steering is not the same as no steering, so the truck is drivable, but a wheel that does not come back to centre is a wheel you are fighting: get it looked at by a qualified mechanic rather than living with it.

  SteeringWorks worseSafety-critical

  • The wheel stays where you left it after a corner instead of unwinding by itself
  • The steering is noticeably heavier turning one way than the other
  • A wet film or drips at the point where the shaft enters the steering box
  • A dry, gritty or notchy feel through the rim as you turn

• Drive gently — repair soon

  The back end sits low and bottoms out

  Owners on a long-running overland forum treat age-related sag on these trucks as simply given: a thread asking for a stock ride-height figure gets the answer that after this many years of settling and adjustment no such measurement is useful any more, and another member assumes their own high-mileage truck has sagged without needing to check. Read that for what it is: a remark about the whole truck settling, made in a thread that was really about front torsion-bar adjustment, not a measurement of these rear springs. Specialist suppliers sell rear coil springs for these trucks graded by how much constant added weight they are meant to carry, with raised options above that, which tells you the same thing from the other direction: the standard spring was chosen for an unladen truck, and a great many of these have spent their working life with a load in the back. Nothing here is a factory figure — there is no published stock height in this entry precisely because the people who own these trucks could not produce one. This is the thinnest evidence base in this set: one owners’ thread and one supplier’s catalogue. Everything below is a measurement you take on your own truck for that reason, rather than a specification you check it against. What sag actually costs you is not comfort. A truck sitting low at the rear has less travel left before the axle meets its stops, so every dip becomes a hit; its headlamps point higher than they should at exactly the moment the back is loaded and the road is dark; and the rear tyres sit closer to the arch than the designer intended. None of that makes the truck undrivable, and none of it arrives suddenly — which is why it is worth measuring rather than eyeballing, because a truck that settles a little each year never looks wrong to the person who drives it every day.

  SuspensionWorks worseSafety-critical

  • The back of the truck sits visibly lower than the front, even empty
  • The rear hits its stops over dips and speed bumps when there is weight in the back
  • Oncoming drivers flash you at night when the truck is loaded
  • A rear tyre touches the arch over bumps with people or luggage aboard
  • The back end wallows and takes a moment to settle on an uneven road

• Drive gently — repair soon

  The rear sits low, knocks and bottoms out under load

  A Montero that squats when it is loaded is usually not broken — it is carrying more than the springs in it were chosen for. The spring supplier for this generation classifies its rear springs by load-carrying capacity as well as by ride height, and warns that even a difference in factory trim changes which spring suits a given truck, which tells you how sensitive the rear end is to what you have added. Every permanent accessory counts: a steel bumper, a winch, skid plates, a second battery, a drawer system, a full water tank. Before you buy springs, check the rubber pads the springs sit on. The same supplier says the lower rear pads take more abuse than any other bushing or pad on the truck, that by this point in a third generation's life the originals are likely worn all the way through, and that the result is the coil sitting directly on the rear control arm — metal on metal, a rougher ride and a lot of noise. A crushed pad makes a healthy spring look tired, and it is the cheapest thing on the list.

  SuspensionWorks worseSafety-critical

  • The rear sits visibly lower than the front once the truck is loaded
  • It bottoms out over bumps with people or gear aboard
  • The back wallows and keeps moving after a bump on a rough road
  • A knock from the back and a harsher ride than the truck used to have

• Drive normally

  Burns oil, blue smoke, no leak to find

  A motoring publication answering owner questions about the late trucks of this generation puts it plainly: these engines tend to burn oil as the distance climbs, and the usual reason is the valve stem seals rather than anything structural — the same answer says it is not regarded as a serious fault. An owners' club thread about a mid-1990s truck losing oil with no visible leak reaches the same list from the other end, with the club's members naming valve stem seals first and then the breather system and turbo shaft wear as the alternatives worth eliminating. The two together are the shape of this problem: it is an ageing-engine trait, not a defect, and its main cost is that it is easy to ignore until the level is low enough to matter. **On the petrol engines the tell that points at the seals is timing.** Oil that seeps past a stem seal collects while the engine sits, so the smoke comes on the first start of the day or after a long wait at lights, and then clears; oil getting past the rings burns all the time, so the smoke stays. **On the diesels that reading does not carry over**, and the club thread cited here is the reason it is spelled out: it is a diesel truck, and the members answering it reach for the crankcase breather and a worn turbo before they reach for the valve stem seals, because a cold diesel smokes for reasons a cold petrol engine does not. If your truck is a diesel, work the breather and the turbo first and treat the seals as the answer that survives eliminating them. Whichever engine you have: check the level often, decide what you are willing to spend, and remember that an engine that uses oil and is never topped up is an engine that stops being fixable.

  EngineWorks worse

  • A cloud of blue smoke on the first start of the day, which then clears
  • A puff of smoke when you pull away after idling in traffic
  • The oil level falls between services with nothing dripping under the truck
  • An oily film inside the intake pipe or the air filter housing
  • A burnt-oil smell behind the truck at a stop

• Drive normally

  Carbon in the inlet and the EGR valve

  Exhaust gas recirculation sends a measured amount of exhaust back into the inlet to lower combustion temperature. Soot in that exhaust meets oil mist in the inlet, and over enough short cold journeys the two build a hard deposit that narrows the manifold and can hold the valve off its seat. The result is a truck that hesitates, idles roughly and no longer answers the throttle the way it used to. The cited source names this on both the third and fourth generations; it is one source and the entry is tiered accordingly. The honest framing is that this is a wear-and-use problem rather than a defect: a truck that does long runs at load rarely gets there, and a truck used for short urban trips gets there sooner. Nothing about it makes the truck unsafe, which is why the triage says drive normally — but it will cost you fuel and throttle response until it is cleaned, and a valve stuck open will keep dumping soot into the inlet you just paid to clean.

  ExhaustWorks worse

  • It hesitates for a beat when you ask for throttle
  • The idle is rough or uneven, especially cold
  • The truck feels flat and slow to respond compared with how it used to

• Drive normally

  Front axle will not engage and the indicator blinks

  On Super Select trucks the front axle is locked and unlocked by a vacuum-operated clutch, and the dash indicator only settles when the transfer lever and the front axle agree about which mode the truck is in. When they disagree, the indicator blinks — which is why a blinking front-wheel display is not a fault in the display. A specialist supplier of parts for these trucks states the same thing on its own product page for the control solenoid: blinking front-wheel lights mean the front axle is having trouble engaging or disengaging. A buyer's guide for this generation tells buyers to try every mode and treats flashing lights as an actuator or position-switch fault. Spanish-language owner reports show the same two complaints reaching drivers in the same words — the front-wheel lights flashing and the lever refusing to go where it is asked — and they are cited here for that and for nothing else: the reports on that page span several generations of this truck, and the causes individual posters propose for their own vehicles are not carried over to this one. This entry is the half where the front axle never comes in. It is a lost capability rather than a hazard: the truck drives and stops exactly as it always did on the rear axle, and nothing is being damaged. The half where the axle will not release is a different problem and has its own entry, because that one does damage things.

  Transfer caseWorks worse

  • The front-wheel indicator on the dash blinks and never settles
  • The transfer lever moves into the four-wheel-drive position but there is no front drive
  • On a loose surface it still spins a rear wheel with four-wheel drive selected
  • The soft clunk from under the truck when four-wheel drive engages no longer happens

• Drive normally

  Front end sits low — settled torsion bars

  The front suspension on this generation is sprung by torsion bars, and a torsion bar is a coil spring that has been straightened out: it settles with age exactly as a coil spring does, and it settles further and unevenly once a winch bumper or a bull bar goes on the front. The one cited club thread is about a later, second-generation truck, not this one — the torsion-bar front end carried over, but nobody in the sources has confirmed the detail on a first-generation truck, which is why this entry carries the site's weakest confidence tier. Owners in that thread describe the layout — an anchor arm at the chassis end of each bar with an adjusting nut and a locknut, the adjuster hidden under a domed rubber cover that is the reason most people cannot find it — and the fact that slackening the locknut and tightening the adjusting nut raises that corner. Two cautions the thread does not spell out and this page will. Raising the front changes the front geometry, so a wheel alignment belongs in the same visit. And ride height is not free travel: the higher you wind it, the less suspension is left and the harder it rides. Suspension is safety-critical; if you are not confident setting both sides equally, have a qualified mechanic do it with the alignment.

  SuspensionWorks worseSafety-critical

  • The truck noses down — the front wheel arch gap is visibly smaller than the rear
  • One front corner sits lower than the other on level ground
  • The front tyres are wearing faster on their inner edges
  • The front suspension bottoms out over bumps it used to take

• Drive normally

  Front window drops into the door

  A comfort failure rather than a mechanical one, but it is the fault most likely to leave a Montero unlockable in the rain, so it earns a place in the first wave. The regulator and motor are supplied as one assembly for the later trucks, and the fitment note on that part is worth reading before ordering: the assembly the specialist stocks is listed for the last three model years of the generation only, so a truck from earlier in the run needs a different part even though the door looks the same. Before buying anything, separate a dead motor from a broken regulator and both of those from a switch or a loom fault in the door jamb, where the wires flex every time the door opens. The order of those three tests costs nothing and decides whether this is a part or a splice. This entry rests on one specialist supplier's parts listing, so it is filed at the weakest tier.

  BodyWorks worse

  • The glass drops into the door and will not come back up
  • Grinding or clicking inside the door when the switch is pressed
  • The glass comes up crooked, binds, or stops part of the way
  • You can hear the motor run but nothing moves

• Drive normally

  Runs lean and fails an emissions test

  One truck in the cited thread ran lean and failed its emissions test on both oxides of nitrogen and unburnt hydrocarbons, and members pointed at a clogged exhaust gas recirculation path and at vacuum leaks. This is a single thread and it is tiered accordingly, but the shape of the advice is worth having because it says something specific about where to start: on a forty-year-old truck the rubber is the suspect before the metering is. Emissions rules are not universal — what a truck must pass, and whether it must be tested at all, depends entirely on the jurisdiction, and a US state test, a Costa Rican inspection and a British test measure different things to different limits. Treat the numbers on your own test slip as the evidence and this page as a method. Nothing here changes how the truck should be driven; it changes what it costs you to run and whether it passes wherever you live.

  Fuel systemWorks worseSafety-critical

  • The truck fails its emissions test, typically on unburnt hydrocarbons or oxides of nitrogen
  • It hesitates, stumbles or flat-spots as you pull away
  • The idle wanders up and down, or sits higher than it should
  • A light metallic pinging under load on a hill

• Drive normally

  Sloppy transfer case lever that will not select

  The transfer lever pivots on a ball at its base, and a specialist supplier of parts for these trucks says plainly what happens to it: a lever that has a lot of side-to-side movement, or that gives trouble shifting between modes, usually has an original ball that has disintegrated. They name it as most common on the later trucks of the run. An owners' forum thread about one of exactly those trucks describes the same fault from the driver's seat, with the owner comparing the lever to stirring a pot of thick, lumpy stew and other members naming the disintegrated ball immediately and pointing at the same part number. One of them adds a caution worth passing on: the replacement is the same part the factory fitted, so this is a repair that restores the lever rather than one that improves it. This is the cheapest fault on this whole set, and it disguises itself as the most expensive one. A lever that will not select four-wheel drive feels exactly like a transfer case that will not engage it, and the difference is a plastic ball the size of a thumb joint against a gearbox out of the truck. So the useful thing here is the order of checking: prove the lever is actually moving the mechanism before anyone opens anything. Nothing about this fault is dangerous and nothing is wearing out because of it — but a truck whose four-wheel drive cannot be selected is a truck that has lost the reason most people bought it.

  Transfer caseWorks worse

  • The lever flops from side to side well beyond where it should stop
  • You cannot find the mode you want, or it lands in the wrong one
  • The lever feels notchy for part of its travel and then goes slack
  • The lever rattles in its housing over rough ground

• Drive normally

  Tailgate hinges rust and the gate drops

  Owner reports filed with the United States road safety agency include rear door hinges corroding badly enough to need replacing. There are two of them and both are from one model year, so the fitment above is narrowed to that year rather than spread across the generation — the same rule applied elsewhere in this set, and the same caveat: if your truck is an adjacent year the inspection below still costs nothing, but nothing here claims your year is affected. The buyer's guide cited alongside establishes that these bodies rot at the arches, sills and mounts; it does not mention hinges, and is not the source for them. It is a small fault next to most of what is on this site, and it earns its place because of what it tells you rather than what it costs. The tailgate carries a heavy spare wheel on a side-hinged door, and those hinges are bolted to a panel that sits at the back of the truck collecting everything the rear wheels throw at it. When the hinges have gone, the water that killed them has been sitting there for years, which means the panel behind them and the bottom of the gate itself are worth looking at before anyone orders parts. The trap is ordering hinges for a truck whose problem is the panel they bolt to: new hinges on soft metal sag again in a season and the money is gone. There is a genuinely cheap version of this and it is worth trying first — a gate that has dropped a little often latches again after the striker is adjusted, and a gate whose drains are clear stops feeding the rust that started all of it.

  BodyWorks worse

  • The tailgate drops at the outer edge as it swings open
  • The gate has to be lifted before it will latch
  • Rust staining and flaking around the hinges and their bolts
  • The gate rattles on rough roads and lets water or dust into the load space
  • The gap around the closed gate is no longer even from top to bottom

• Drive normally

  The horn sounds on its own

  A recurring complaint on this generation, and one whose repair sits somewhere most owners should not go. The horn contacts live under the pad in the middle of the steering wheel — directly on top of the driver's airbag module — and complaints describe the horn going off when the wheel is turned, when the truck hits a bump, and most often on cold mornings with the vehicle parked and switched off. One owner's account explains the mechanism: the covering over the module contracts in the cold and squeezes the horn contacts underneath it. Another had a mechanic replace the horn relay three times without curing it, which is worth knowing before you assume the cheap fix will hold. Owners report living with it by pulling the horn fuse, which trades one problem for another. Whether a vehicle whose horn does not work passes inspection depends on where you are — Costa Rica's RTV, a British MOT and a US state inspection each set their own rules — so check locally rather than assuming. What does not vary is that the pad in the middle of that wheel is a live restraint device: this repair belongs to a qualified mechanic.

  Interior and trimWorks worseSafety-critical

  • The horn sounds by itself with the vehicle parked and switched off
  • The horn sounds when the wheel is turned to a certain angle, or over bumps
  • It happens most on the coldest mornings and settles as the day warms
  • The only thing that stops it is pulling the horn fuse or disconnecting the battery

No problems match that symptom or search.