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:
Automatic Transfer Case
The transfer case knob is located next to the steering column.
Use the dial to shift into and out of Four-Wheel Drive.
You can choose among five driving settings:
Indicator lights in the dial sho ...
Fuel Additives
To provide cleaner air, all gasolines in the United States are now required to contain additives that help prevent engine and fuel system deposits from forming, allowing the emission control system to ...
Hydraulic Power Steering
Your vehicle has hydraulic power steering. It may require maintenance. See Power Steering Fluid on page 10‑21.
If power steering assist is lost due to a system malfunction, the vehicle can be s ...





