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 TiresProblems with Route Guidance
Inappropriate route guidance can occur under one or more of the following conditions:
• The turn was not made on the road indicated.
• Route guidance might not be available when using automatic rerouting for the next
right or left turn.
• The route might not be changed when using automati ...
OnStar® Destination Download
The destination download lets an OnStar® subscriber ask an OnStar Advisor to
download a destination to the navigation system. OnStar will send address information
and location coordinates of the destination into the navigation system.
Using Destination Download
If the navigation radio screen i ...
Instrument Panel Tie Bar Replacement (Right Hand Drive)
Removal Procedure
Remove instrument panel compartment. Refer to Instrument Panel
Compartment Replacement.
Remove instrument panel wiring harness (2) from instrument panel tie bar
(1).
Disconnect electrical connectors.
Remove instrument panel tie bar (1).
Remov ...