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
Create 5 x 18 mm (4/16 x 11/16 in) slots for MIG-Brazing along the edges
of the front wheelhouse panel rear reinforcement as
noted from the original panel.
Create a 5 x 18 mm (4/16 x 11/16 in) slot for MIG-Brazing where front
wheelhouse front panel and front wheelhouse panel ...
Vehicle Positioning
At times, the position of the vehicle on the map could be inaccurate due to one
or more of the following reasons:
• The road system has changed.
• The vehicle is driving on slippery road surfaces such as sand, gravel, or snow.
• The vehicle is traveling on winding roads or long straight roads.
...
Engine Coolant
The cooling system in the vehicle is filled with DEX-COOL engine coolant. This
coolant is designed to remain in the vehicle for 5 years or 240 000 km (150,000
mi), whichever occurs first.
The following explains the cooling system and how to check and add coolant when
it is low. If there is a ...