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 TiresSteering Column in Lock Position Caution
Caution: With wheels of the vehicle facing straight ahead, secure
the steering wheel utilizing steering column anti-rotation pin, steering
column lock, or a strap to prevent rotation. Locking of the steering column will
prevent damage and a possible malfunction of the SIR
system. The steering ...
Exterior Care
Washing the Vehicle
To preserve the vehicle's finish, wash it often and out of direct sunlight.
Notice: Do not use petroleum-based, acidic, or abrasive cleaning agents
as they can damage the vehicle's paint, metal, or plastic parts.
If damage occurs, it would not be covered by the vehic ...
Installation Procedure
Prepare all mating surfaces as necessary.
Align the front hinge pillar body reinforcement.
Create 6 x 20 mm (4/16 x 12/16 in) slots for MIG-brazing in locations
where you can not apply a resistance spot
welder.
Clean and prepare the attaching surfaces for spot welding a ...