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 TiresRear Side Door Trim Replacement
Rear Side Door Inside Handle Bolt Finish Cap
Procedure
Pull handle back to remove cap. Use suitable tool to unsnap.
Rear Side Door Inside Handle Screw
Caution: Refer to Fastener Caution in the Preface section.
Tighten
2.5 N·m (23 lb in)
Rear Side Door Pull Handle Screw
T ...
Ignition Positions (Key Access)
The ignition switch has four different positions.
Notice: Using a tool to force the key to turn in the ignition could
cause damage to the switch or break the key. Use the correct key, make sure it is
all the way in, and turn it only with your hand.
If the key cannot be turned by hand, see yo ...
Removal Procedure
Warning: Refer to Approved Equipment for Collision Repair Warning in the
Preface section.
Warning: Refer to Glass and Sheet Metal Handling Warning in the Preface section.
Disable the SIR System. Refer to SIR Disabling and Enabling.
Disconnect the negative battery cable. Refer to Battery N ...