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. ...

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 ...

Gasoline Specifications (U.S. and Canada Only)
At a minimum, gasoline should meet ASTM specification D 4814 in the United States or CAN/CGSB-3.5 or 3.511 in Canada. Some gasolines contain an octane-enhancing additive called methylcyclopentadienyl ...