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 communicate with GMC by dialing:
1-800-462-8583. TTY users in Canada can dial 1-800-263-3830.
See also:
Rear Window Defogger
For vehicles with a rear window defogger, a warming grid is used to remove fog from the rear window.
(Rear): Press to turn the rear window defogger on or off. An indicator light on the button comes ...
Reading Lamps
For vehicles with reading lamps in the overhead console, press the button located next to the lamp to turn it on or off.
The vehicle may also have reading lamps in other locations. To turn the lamps ...
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 ...





