See also:

Leaving the Vehicle With the Engine Running
WARNING It can be dangerous to leave the vehicle with the engine running. The vehicle could move suddenly if the shift lever is not fully in P (Park) with the parking brake firmly set. And, if yo ...

Customer Assistance for Text Telephone (TTY) Users (U.S. and Canada)
To assist customers who are deaf, hard of hearing, or speech impaired and who use Text Telephones (TTYs), GMC has TTY equipment available at its Customer Assistance Center. Any TTY user can communicat ...

All Terrain chassis and suspension
Based on the chassis of the 2011 Sierra HD trucks, the All Terrain HD features a fully boxed steel frame with exceptional strength and torsional stiffness. It incorporates the production models' n ...