How to Check Lubricant

2500HD with 6.0 L
2500HD with 6.0 L

All Other Series and Engines
All Other Series and Engines

To get an accurate reading, the vehicle should be on a level surface.

• For all 4.3 L, 4.8 L and 5.3 L 1500 Series applications, the proper level is 1.0mm to 19.0mm (0.04 in to 0.7 in) below the bottom of the fill hole, located on the rear axle. Add only enough fluid to reach the proper level.

• For all 6.0 L and 6.2 L 1500 Series applications, the proper level is from 15mm to 40mm (0.6 in to 1.6 in) below the bottom of the fill plug hole, located on the rear axle. Add only enough fluid to reach the proper level.

• For all 6.0 L 2500HD Series applications, the proper level is from 0mm to 13mm (0 to 0.5 in) below the bottom of the fill plug hole, located on the rear axle.

Add only enough fluid to reach the proper level.

• For all 6.6 L Duramax Diesel 2500HD Series applications and all 3500 Series applications, the proper level is from 17mm to 21mm (0.6 in to 0.8 in) below the bottom of the fill plug hole, located on the rear axle. Add only enough fluid to reach the proper level.

    See also:

    Fuel
    Use of the recommended fuel is an important part of the proper maintenance of this vehicle. To help keep the engine clean and maintain optimum vehicle performance, we recommend the use of gasoline ...

    Engine Oil Life System
    The engine oil life system calculates engine oil life based on vehicle use and, on most vehicles, displays a DIC message when it is necessary to change the engine oil and filter. The oil life system ...

    Treadwear
    The treadwear grade is a comparative rating based on the wear rate of the tire when tested under controlled conditions on a specified government test course. For example, a tire graded 150 would wear ...