See also:

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 ...

Weatherstrips
Apply silicone grease on weatherstrips to make them last longer, seal better, and not stick or squeak. See Recommended Fluids and Lubricants on page 11‑12. ...

Overheated Engine Protection Operating Mode
This emergency operating mode lets the vehicle be driven to a safe place in an emergency situation. If an overheated engine condition exists, an overheat protection mode which alternates firing groups ...