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:

    Trailer Gain Adjustment Procedure
    Trailer Gain should be set for a specific trailering condition and must be adjusted any time vehicle loading, trailer loading, or road surface conditions change. Setting the Trailer Gain properly is ...

    Tow/Haul Mode
    Pressing this button at the end of the shift lever turns on and off the Tow/Haul Mode. This indicator light on the instrument panel cluster comes on when the Tow/Haul Mode is on. Tow/Haul is a f ...

    Automatic Transmission Shift Lock Control Function Check
    WARNING When you are doing this inspection, the vehicle could move suddenly. If the vehicle moves, you or others could be injured. 1. Before starting this check, be sure there is enough room around ...