How to Check Lubricant

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

1500 Series
1500 Series

A. Fill Plug
B. Drain Plug

All Except 1500 Series
All Except 1500 Series

A. Fill Plug
B. Drain Plug

• When the differential is cold, add enough lubricant to raise the level from 0mm (0 in) to 3.2mm (1/8 in) below the fill plug hole.
• When the differential is at operating temperature (warm), add enough lubricant to raise the level to the bottom of the fill plug hole.

    See also:

    Engine Drive Belt Routing
    V6 Engines V8 Engines If the vehicle has a diesel engine, see the Duramax diesel supplement for more information. If the vehicle is a hybrid, see the hybrid supplement 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 p ...

    Storing and Deleting Phone Numbers
    The system can store up to 30 phone numbers as name tags in the Hands&-Free Directory that is shared between the Bluetooth and OnStar systems. The following commands are used to delete and stor ...