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:
Daytime Running Lamps (DRL)
Daytime Running Lamps (DRL) system makes the low-beam headlamps come on at a
reduced brightness in daylight when the following conditions are met:
○ The ignition is on.
○ The exterior ...
Driving on Grades
Reduce speed and shift to a lower gear before starting down a long or steep downgrade.
If the transmission is not shifted down, the brakes might have to be used so much
that they would get hot and ...
Power Liftgate Operation
On vehicles with a power liftgate, the vehicle must be in P (Park) to use the
power feature. The taillamps flash when the power liftgate moves.
Notice: If you open the liftgate without checking f ...





