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 TiresMalfunction Indicator Lamp
A computer system called OBD II (On-Board Diagnostics-Second Generation) monitors
the operation of the vehicle to ensure emissions are at acceptable levels, helping
to maintain a clean environment.
The malfunction indicator lamp comes on when the vehicle is placed in ON/RUN
for key access or ...
Roof
Sunroof
The sunroof only operates when the ignition is in ON/RUN or ACC/ ACCESSORY, or
when Retained Accessory Power (RAP) is active.
To open or close the sunroof, press the open or close sunroof switch (1) to the
first detent position.
To express open or close the sunroof with the safety f ...
Navigation System
If the vehicle has a navigation system, there is a separate navigation manual
that includes information on the radio, audio players, and navigation system.
The navigation system provides detailed maps of most major freeways and roads.
After a destination has been set, the system provides turn-b ...