See also:

California Fuel Requirements
If the vehicle is certified to meet California Emissions Standards, it is designed to operate on fuels that meet California specifications. See the underhood emission control label. If this fuel is no ...

Customer Assistance Offices (U.S. and Canada)
GMC encourages customers to call the toll-free number for assistance. However, if a customer wishes to write or e-mail GMC, the letter should be addressed to: United States GMC Customer Assistance ...

Shifting Into Two-Wheel Drive High
Turn the knob to the Two-Wheel Drive High position. This can be done at any speed, except when shifting from Four-Wheel Drive Low. See “Shifting Out of Four-Wheel Drive Low” for more information. ...