Rear Axle
When to Check Lubricant
It is not necessary to regularly check rear axle fluid unless you suspect there is a leak or you hear an unusual noise. A fluid loss could indicate a problem. Have it inspected and repaired.
How to Check Lubricant

To get an accurate reading, the vehicle should be on a level surface.
The proper level is from 0 to 3/8 inch (0 to 10 mm) below the bottom of the filler plug hole, located on the rear axle.
What to Use
To determine what kind of lubricant to use.
See also:
Auxiliary Devices (Radio with CD and Touchscreen)
For vehicles equipped with the
MyLink or IntelliLink infotainment
system, see the separate MyLink/IntelliLink Features and Functions
Guide for more information.
The optional AUX input allows
...
Running the Engine While Parked
It is better not to park with the engine running. But if
you ever have to, here are some things to know.
CAUTION:
Idling the engine with the climate control
system off could allow dangerous exha ...
OnStar Personal Identification
Number (PIN)
A PIN is needed to access some of
the OnStar services, like Remote
Door Unlock and Stolen Vehicle
Assistance. You will be prompted to
change the PIN the first time when
speaking with an Advi ...
