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 TiresInstallation Procedure
Remove the front wheelhouse rear panel brace (1) from service panel.
Create 6 x 20 mm (4/16 x 12/16 in) slots for MIG-brazing along the edges
of the front wheelhouse (1).
Clean and prepare the attaching surfaces for brazing.
Note: In MIG-brazing areas 50 mm (2 in) must b ...
Navigation
OnStar navigation requires the Directions and Connections service plan.
Press to receive directions or have
them sent to the vehicle navigation screen, if equipped.
Destinations can also be forwarded to the vehicle from MapQuest.com.
The OnStar mapping database is continuously updated. For cov ...
Rear Side Door Weatherstrip Replacement - Door Side
Rear Side Door Check Bolt
Caution: Refer to Fastener Caution in the Preface section.
Tighten
25 N·m (19 lb ft)
Rear Side Door Weatherstrip - Door Side
Procedure
Unclip weatherstrip from rear side door.
When removing protective liners from adhesive tape, be care ...