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 TiresMaintenance Schedule
Owner Checks and Services
At Each Fuel Stop
• Check the engine oil level.
Once a Month
• Check the tire inflation pressures.
• Inspect the tires for wear.
• Check the windshield washer fluid level.
Engine Oil Change
When the CHANGE ENGINE OIL SOON DIC message or Code 82 DIC message dis ...
Front Fender Front Lower Bracket Replacement
Preliminary Procedure
Remove the front bumper fascia. Refer to Front Bumper Fascia
Replacement.
Remove the headlamp. Refer to Headlamp Replacement
Remove the front fender. Refer to Front Fender Replacement.
Front Fender Bracket Bolt
Caution: Refer to Fastener Caut ...
Rear Bumper Fascia Replacement
Preliminary Procedure
Remove the tail lamps. Refer to Tail Lamp Replacement.
Rear Bumper Fascia Retainer (Qty: 2)
Rear Wheelhouse Liner Bolt (Qty: 6)
Caution: Refer to Fastener Caution in the Preface section.
Tighten
2.5 N·m (23 lb in)
Rear Bumper Fascia
Procedure
Pull th ...