Engine Oil
For diesel engine vehicles, see “Engine Oil” in the Duramax Diesel Supplement.
To ensure proper engine performance and long life, careful attention must be paid to engine oil.
Following these simple, but important steps will help protect your investment:
• Always use engine oil approved to the proper specification and of the proper viscosity grade. See “Selecting the Right Engine Oil” in this section.
• Check the engine oil level regularly and maintain the proper oil level. See “Checking Engine Oil” and “When to Add Engine Oil” in this section.
• Change the engine oil at the appropriate time. See Engine Oil Life System on page 10‑10.
• Always dispose of engine oil properly. See “What to Do with Used Oil” in this section.
See also:
Control of a Vehicle
Braking, steering, and accelerating are important factors in helping to control a vehicle while driving. ...
High-Beam On Light
The high&-beam on light comes on when the high-beam headlamps are in use.
See Headlamp High/Low-Beam Changer on page 6‑2 for more information. ...
Warning Lights, Gauges, and
Indicators
Warning lights and gauges can signal that something is wrong before it becomes serious enough to cause an expensive repair or replacement. Paying attention to the warning lights and gauges could preve ...





