Going to 33s: what 285/75R16 costs you

Wheels and tiresSafety-criticalCost$$–$$$Difficulty 2/5FitsGen 3

Safety notice — Wheels and tires.

This affects a safety-critical system. Reference material only: for safety-critical work, consult a qualified mechanic.

Esto afecta un sistema crítico para la seguridad. Material de referencia únicamente: en trabajos críticos para la seguridad, consulte a un mecánico calificado.

Safety notice — Suspension.

This affects a safety-critical system. Reference material only: for safety-critical work, consult a qualified mechanic.

Esto afecta un sistema crítico para la seguridad. Material de referencia únicamente: en trabajos críticos para la seguridad, consulte a un mecánico calificado.

Community consensus. This entry is not backed by factory documentation — treat its values and steps as a starting point, not as if they came from the factory manual.

Consenso de la comunidad. Esta entrada no se apoya en documentación de fábrica — tome los valores y los pasos como punto de partida, no como si vinieran del manual de fábrica.

The factory size on a third-generation Montero is listed in two of the citations below, and the usual 33-inch answer for a 16-inch wheel is 285/75R16. The tire calculator cited here gives the overall diameter of both sizes, the difference between them as a figure and as a percentage, and what the speedometer reads once the bigger tire is on — those are the numbers this decision actually turns on, and they are in the citation rather than repeated here. What the calculator cannot tell you is the second half of the bill: a common 33-inch all-terrain in this size is a light-truck tire with a stiff ten-ply casing and a per-tire weight the fourth citation states, and every one of those pounds is unsprung and rotating.

What it needs first

Nothing else has to be done first.

What it breaks or affects

Everything below is a consequence of fitting this, not a reason against it. Read it before you buy, not after.

System	Consequence	What happens
Interior and trim	Gets worse	The instrument cluster counts wheel revolutions and multiplies by the factory rolling circumference, so a taller tire makes both the speedometer and the odometer read low. The tire calculator cited below works the error out for you — it gives the true road speed behind a given indicated speed, and the percentage error that produces it. Treat every distance-based service interval as arriving sooner than the odometer claims.
Drivetrain	Gets worse	A larger rolling diameter multiplies through the whole driveline, so every gear and the low range with it end up taller than the factory chose. That is a permanent change in how the truck pulls, and the only real fix is the differential ratio — which is the linked entry.Modificationgen3-drivetrain-regear-third-member-swap
Suspension	Gets worse	The per-tire weight of a common ten-ply 33 in this size is in the fourth citation, and it is weight at the worst possible place: unsprung, and turning. Springs and dampers now control more mass than they were valved for, and a lift that was chosen for the standard tire does not account for it.
Wheels and tires	Has to be reset	The pressure on the door placard was calculated for the factory tire, and the light-truck tire cited below carries a completely different maximum-load-and-pressure pair. Running placard pressure in a ten-ply casing gives a hard ride and a narrow contact patch; guessing lower risks overheating a tire under load. Have the pressure set against the tire's own load table for the weight your truck actually carries.

The honest tradeoffs

The speedometer and the odometer both go optimistic in your favour and against you at once: you are travelling faster than the dial says, and the truck is recording fewer kilometres than it covers, which quietly stretches every service interval you keep by mileage. Acceleration, braking and fuel all get worse in the same move, because you have added rotating mass at the biggest radius on the vehicle and lengthened the effective final drive at the same time. The load rating is not decoration — a ten-ply light-truck casing is rated at a pressure far above anything the door placard contemplates, and the placard pressure was calculated for the factory tire, so it is no longer the right answer for this one. Some of this is recoverable: gearing can be put back (see the regear entry linked in the table below), and a tire shop can reset the pressures properly. Some of it is not: the extra mass stays for as long as the tires do, and clearance at full lock and at full compression is something you check on your own truck before you buy, because trim, wheel offset and ride height all move it and no table can answer it for you. Tires and load ratings are safety-critical: have the fitment, the load rating and the pressures confirmed by a qualified tire shop rather than working from a forum post — including this one.

Safety notice — Wheels and tires.

Safety notice — Suspension.

What it needs first

What it breaks or affects

The honest tradeoffs

Sources