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. See Tire Inspection and Tire Rotation.
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 TiresIndicator/Warning Message Description and Operation
Indicator LIGHT ON
Refer to the owner's manual for the descriptions and explanations of all
indicator lights.
For diagnosis and repair information related to an indicator light, refer
to the System Diagnosis and the Description of Operation that the message relates
to.
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Tire Terminology and Definitions
Air Pressure
The amount of air inside the tire pressing outward on each square inch
of the tire. Air pressure is expressed in kPa (kilopascal) or psi (pounds per
square inch).
Accessory Weight
The combined weight of optional accessories. Some examples of optional
access ...
Control Valve Body Assembly Disassemble (Gen 1)
Control Valve Body Assembly Disassemble
Callout
Component Name
1
Control Solenoid Valve Support
2
Control Valve Body Bolt M5 x 40.5 (Qty: 1)
3
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