GMC 2003 Sierra - Manual (Page 434)

Front Axle
When to Check Lubricant
to iha Mamtenanca Schectuie to delariiiiine how
often to checli the lubricantr See Fsft Ar Scheduled
Maintenance Semcee on p^ge
How to Check Lubricant
tl the level Is below !he bolton of Ihe hller plug holen
you may need to add some lubricanh
When the ditfeTientia! is ocici, add enough lubricant to
raise Ihe level lo 0 lo inch ^9-5 mm) below Ihe lillei
plug hole.
When the diffaronltal is at operating temperature
(warm), add enough lubricant lo raise ihe level lo the
bottom of the fills r plug hole.
What to Use
Refer to the Maintenance Schedule to detenmine wha1
kind of lubncant to use. See
Pad D: Recommended
Fluids and Lubricants on pegs G-is.
To gel an accurele reading, fhe vehicle should be on a
level surface.
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