Underbody Maintenance

Use plain water to flush dirt and debris from the vehicle's underbody.

Your dealer or an underbody car washing system can do this. If not removed, rust and corrosion can develop.

    See also:

    When to Add Engine Oil
    If the oil is below the cross-hatched area at the tip of the dipstick, add 1 L (1 qt) of the recommended oil and then recheck the level. See “Selecting the Right Engine Oil” in this section for ...

    New for 2011
    The Sierra Hybrid gets GM's OnStar 9.0 telematics system that GM says provides better voice recognition. GM also said they have worked to cut down on the amount of wind noise occupants hear. ...

    Engine Cooling When Trailer Towing
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