See also:

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 ...

Checking Engine Oil
It is a good idea to check the engine oil level at each fuel fill. In order to get an accurate reading, the vehicle must be on level ground. The engine oil dipstick handle is a yellow loop. See Engi ...

Recommended Fuel
Use regular unleaded gasoline with a posted octane rating of 87 or higher. If the octane rating is less than 87, an audible knocking noise, commonly referred to as spark knock, might be heard when dri ...