Engine Coolant Heater
The engine heater can provide easier starting and better fuel economy during engine warm-up in cold weather conditions at or below −18°C (0°F). Vehicles with an engine heater should be plugged in at least four hours before starting.
An internal thermostat in the plug-end of the cord may exist which will prevent engine coolant heater operation at temperatures above −18°C (0°F).
If the vehicle has a diesel engine, see the Duramax Diesel supplement for more information.
See also:
Shifting Out of Four-Wheel Drive Low
To shift from Four-Wheel Drive Low to Four-Wheel Drive High, AUTO or Two-Wheel Drive High, the vehicle must be stopped or moving less than 5 km/h (3 mph) with the transmission in N (Neutral) and the i ...
Tire Rotation and Required Services Every 12 000 km/7,500 mi
Rotate the tires, if recommended for the vehicle, and perform the following services. See Tire Rotation on page 10‑50.
• Check engine oil level and oil life percentage. If needed, change engi ...
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 ...