See also:

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 methylcyclopen ...

Engine Power Messages
ENGINE POWER IS REDUCED This message displays when the vehicle's engine power is reduced. Reduced engine power can affect the vehicle's ability to accelerate. If this message is on, but t ...