Rear Axle - Hummer 2008 H2 Owner's Manual

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.
All axle assemblies are filled by volume of fluid during
production. They are not filled to reach a certain
level. When checking the fluid level on any axle,
variations in the readings can be caused by factory fill
differences between the minimum and the maximum
fluid volume. Also, if a vehicle has just been driven
before checking the fluid level, it may appear lower than
normal because fluid has traveled out along the axle
tubes and has not drained back to the sump area.
Therefore, a reading taken five minutes after the vehicle
has been driven will appear to have a lower fluid level
than a vehicle that has been stationary for an hour
or two. Remember that the rear axle assembly must be
supported to get a true reading.
How to Check Lubricant
To get an accurate reading, the vehicle should be on a
level surface.
When the differential is cold, the proper level is from
5/8 inch to 1-5/8 inch (15 mm to 40 mm) below the
bottom of the filler plug hole, located on the rear axle.
Add only enough fluid to reach the proper level.
What to Use
Refer to the Maintenance Schedule to determine what
kind of lubricant to use. See Recommended Fluids
and Lubricants on page 6-12.
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