See also:

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. ...

Customer Assistance Offices (U.S. and Canada)
GMC encourages customers to call the toll-free number for assistance. However, if a customer wishes to write or e-mail GMC, the letter should be addressed to: United States GMC Customer Assistance ...

Compass Variance (Zone) Procedure
1. Do not set the compass zone when the vehicle is moving. Only set it when the vehicle is in P (Park). Press the vehicle information button until PRESS TO CHANGE COMPASS ZONE displays. 2. Find ...