Rear Axle - GMC Sierra 2008 Owner's Manual

Rear Axle

How to Check Lubricant
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
2500HD with 6.0L
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.
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