2011 GMC Terrain — SLT FWD

The 2011 GMC Terrain SLT FWD shipped with 2 different factory tire sizes, depending on the wheel package it left the factory with (this can also reflect a staggered front/rear setup). Check your tire sidewall or door placard to confirm which one applies to your vehicle.

This trim shipped with more than one tire size (staggered fitment, front/rear, or optional wheel package). Confirm which one matches your vehicle by checking your tire sidewall or door placard.

235/55R18

Section width235 mm
Aspect ratio (sidewall height)55% (129.3 mm)
Rim diameter18"
Overall tire diameter~28.2"
Revolutions per mile~716

Compare prices at:

235/55R19

Section width235 mm
Aspect ratio (sidewall height)55% (129.3 mm)
Rim diameter19"
Overall tire diameter~29.2"
Revolutions per mile~691

Compare prices at:

What this size means for your GMC Terrain

On the 2011 GMC Terrain SLT FWD, the factory 235/55R18 measures about 28.2″ in overall diameter with a 129.3 mm (5.1″) sidewall, and completes roughly 716 revolutions per mile. Its 55-series aspect ratio gives a balanced everyday-passenger profile — enough sidewall to soak up road shock while keeping steering response crisp. In tire terms it is a passenger (P-metric / Euro-metric) size.

The 235/55R18 and 235/55R19 differ by about 1″ (3.5%) in overall diameter; a gap this size is enough to affect speedometer and odometer readings, so confirm which one your vehicle actually left the factory with.

Other 2011 GMC Terrain trims

GMC Terrain tire sizes by year

See every GMC Terrain year & trim →

How to read a tire size

A tire size like 225/45R17 breaks down into three parts: the first number is the section width in millimeters (the tire's width from sidewall to sidewall), the second is the aspect ratio — the sidewall's height as a percentage of that width — and the number after the "R" is the rim diameter in inches. A letter prefix (P or LT) indicates Passenger or Light Truck construction; its absence usually means Euro-metric sizing.

Some trucks and off-road tires instead use "flotation" sizing, like 37X12.50R17 — here the numbers are the tire's overall diameter and width in inches directly, with the rim diameter last.

Always verify against the tire information placard on your driver's-side door jamb or your owner's manual before purchasing — tire size can vary by factory option package even within the same trim.