See also:

Manual Operation
The air delivery mode or fan speed can be manually adjusted. (Fan Control): Press to increase or decrease the fan speed. Pressing or while in automatic control places the fan speed under manual ...

Special Application Services
• Severe Commercial Use Vehicles Only: Lubricate chassis components every 5 000 km/3,000 mi. • Have underbody flushing service performed once a year. ...

Engine Overheating
If the vehicle has the Duramax® Diesel engine, see the Duramax Diesel Supplement for more information. The vehicle has several indicators to warn of engine overheating. There is a coolant temperatu ...