Rear Axle - GMC 2009 Yukon XL Owner's Manual

To disconnect the jumper cables from both vehicles
do the following:
1. Disconnect the black negative (−) cable from the
vehicle that had the bad battery.
2. Disconnect the black negative (−) cable from the
vehicle with the good battery.
3. Disconnect the red positive (+) cable from the
vehicle with the good battery.
4. Disconnect the red positive (+) cable from the other
vehicle.
5. Return the remote positive (+) terminal cover, if the
vehicle has one, to its original position.

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.
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