Tire Inspection

We recommend that the tires, including the spare tire, if the vehicle has one, be inspected for signs of wear or damage at least once a month.

Replace the tire if:

- The indicators at three or more places around the tire can be seen.
- There is cord or fabric showing through the tire's rubber.
- The tread or sidewall is cracked, cut, or snagged deep enough to show cord or fabric.
- The tire has a bump, bulge, or split.
- The tire has a puncture, cut, or other damage that cannot be repaired well because of the size or location of the damage.

    See also:

    Diagnostics
    OnStar Vehicle Diagnostics will perform a vehicle check every month. It will check the engine, transmission, antilock brakes, and major vehicle systems. It also checks the tire pressures, if the v ...

    Fuel System Messages
    FUEL LEVEL LOW This message displays when the vehicle is low on fuel. Refuel as soon as possible TIGHTEN GAS CAP This message displays when the fuel cap is not on tight. Tighten the fuel ca ...

    Heated Mirrors
    (Rear Window Defogger): Press to heat the mirrors. See Dual Automatic Climate Control System. ...