See also:

Reporting Safety Defects to General Motors
In addition to notifying NHTSA (or Transport Canada) in a situation like this, please notify General Motors. Call 1-800-GMC-8782 (1-800-462-8782), or write: GMC Customer Assistance Center P.O. Box ...

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. ...

What to Use
WARNING Adding only plain water or some other liquid to the cooling system can be dangerous. Plain water and other liquids, can boil before the proper coolant mixture will. The coolant warning syste ...