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 TiresWhere Are the Airbags?
The driver frontal airbag is in the center of the steering wheel.
The front outboard passenger frontal airbag is in the passenger side instrument
panel.
The driver knee airbag is below the steering column. The front outboard passenger
knee airbag is below the glove box.
Driver Side Show ...
Front Side Door Trim Replacement
Front Side Door Pull Handle Bolt
Caution: Refer to Fastener Caution in the Preface section.
Tighten
2 N·m (18 lb in)
Front Side Door Inside Handle Bolt Finish Cap
Tip
Pull handle back to remove cap. Use suitable tool to unsnap.
Front Side Door Inside Handle Bolt
Tighten
...
Work Stall Test Warning
Warning: One or more of the following guidelines may apply when performing
specific required tests in the work stall:
When a test requires spinning the drive wheels with the vehicle jacked up,
adhere to the following precautions:
Do not exceed 56 km/h (35 mph) when spinning one drive wheel ...