Factors such as maintenance, temperatures, driving speeds, vehicle loading, and road conditions affect the wear rate of the tires.

Treadwear indicators are one way to tell when it is time for new tires.
Treadwear indicators appear when the tires have only 1.6mm (1/16 in) or less of tread remaining.
The rubber in tires ages over time.
This also applies to the spare tire, if the vehicle has one, even if it is never used. Multiple factors including temperatures, loading conditions, and inflation pressure maintenance affect how fast aging takes place. GM recommends that tires, including the spare if equipped, be replaced after six years, regardless of tread wear. The tire manufacturer date is the last four digits of the DOT Tire Identification Number (TIN) which is molded into one side of the tire sidewall. The first two digits represent the week (01–52) and the last two digits, the year. For example, the third week of the year 2010 would have a four-digit DOT date of 0310.
Vehicle Storage
Tires age when stored normally mounted on a parked vehicle. Park a vehicle that will be stored for at least a month in a cool, dry, clean area away from direct sunlight to slow aging. This area should be free of grease, gasoline, or other substances that can deteriorate rubber.
Parking for an extended period can cause flat spots on the tires that may result in vibrations while driving. When storing a vehicle for at least a month, remove the tires or raise the vehicle to reduce the weight from the tires.
Tire Rotation
Buying New TiresBody Side Trim Panel Replacement - Left Side
Preliminary Procedure
Remove the rear side door sill trim plate. Refer to Rear Side Door Sill
Trim Plate Replacement.
Remove the rear seat back. Refer to Rear Seat Replacement.
Remove the quarter window garnish molding. Refer to Quarter Window
Garnish Molding Replacement.
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If the Vehicle Is Stuck
Slowly and cautiously spin the wheels to free the vehicle when stuck in sand,
mud, ice, or snow.
If stuck too severely for the traction system to free the vehicle, turn the traction
system off and use the rocking method.
WARNING
If the vehicle's tires spin at high speed, they can explode, ...
Replacing LATCH System Parts After a Crash
WARNING
A crash can damage the LATCH system in the vehicle. A damaged LATCH system
may not properly secure the child restraint, resulting in serious injury or even
death in a crash. To help make sure the LATCH system is working properly after a
crash, see your dealer to have the system inspec ...