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 TiresTire Messages
SERVICE TIRE MONITOR SYSTEM
This message displays if there is a problem with the Tire Pressure Monitor System
(TPMS).
TIRE LEARNING ACTIVE
This message displays when the system is learning new tires.
TIRE PRESSURE LOW ADD AIR TO TIRE
On vehicles with the Tire Pressure Monitor System (TPMS), t ...
Bumpers and Fascias
Specifications
Front Bumper Energy Absorber Replacement
Preliminary Procedure
Remove the front bumper fascia. Refer to Front Bumper Fascia Replacement.
Front Bumper Energy Absorber
Procedure
Unclip from front bumper fascia. ...
Rear Window Defogger Description and Operation
Rear Window Defogger System Components
The rear window defogger system consists of the following components:
HVAC Control Module
HVAC Control Head
Rear Window Defogger Relay
Rear Defogger Grid
F28UA 40A Fuse
Rear Window Defogger Operation
The rear defog control system utilizes a sin ...