Rear Axle - GMC 2012 Sierra Series Owner's Manual

10-34 Vehicle Care
All Except 1500 Series
A. Fill Plug
B. Drain Plug
When the differential is cold, add
enough lubricant to raise the
level from 0 mm (0 in) to 3.2 mm
(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.
What to Use
Refer to Recommended Fluids and
Lubricants on page 11 12 to
determine what kind of lubricant
to use.

Rear Axle

When to Check Lubricant
It is not necessary to regularly
check rear axle fluid unless a leak is
suspected or an unusual noise is
heard. 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.
I n f o r ma t i o n P r o v i d e d b y :
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.