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 Compartment Lid Weatherstrip Replacement
   
Rear Compartment Lid Weatherstrip
Procedure
	Start at the upper corner of the rear compartment opening and pull the 
	weatherstrip away from the rear
	compartment opening flange.
	Position the weatherstrip in the upper corner of the r 2. ear 
	compartment opening.
	Working downward alon ...
   
Deployment Outside Vehicle for Seat Belt Pretensioners
   Deploy the seat belt pretensioners outside of the vehicle when the vehicle 
will be returned to service. Situations that require deployment
outside of the vehicle include the following:
	Using the SIR diagnostics, you determine that the seat belt pretensioner 
	is malfunctioning.
	The pretens ...
   
Driver Information Center (DIC)
   The DIC display is in the center of the instrument cluster. It shows the status 
of many vehicle systems. The controls for the DIC are on the turn signal lever.
1. SET/CLR: Press to set, or press and hold to clear, the menu item displayed.
2.  /
 : Use the thumbwheel to scroll through 
the it ...