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:
Roadside Assistance Program
U.S.: 1-888-881-3302
TTY Users (U.S.): 1-888-889-2438
Canada: 1-800-268-6800
Mexico: 01-800-466-0801
As the owner of a new GMC, you are automatically enrolled in the Roadside Assistance program.
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Three-Way Calling
Three-way calling must be supported on the cell phone and enabled by the wireless
service carrier.
1. While on a call, press .
2. Say “Three&-way call.”
3. Use the dial or call command to ...
Adjusting the Speakers (Balance/Fade)
BAL/FADE (Balance/Fade):
To adjust the balance or fade:
1. Press until the speaker control tabs display.
2. Continue pressing to highlight the tab, or press the softkey under the tab.
3. To adju ...