GMC 2004 Savana - Manual (Page 295)

Front Axle
When to Check and Change Lubricant
Refer to the Maintenance Schedule to determine how
often to check the lubricant and when to change it. See
Scheduled Maintenance on page 6-4.
How to Check Lubricant
To get an accurate reading, the vehicle should be on a
level surface.
If the level is below the
bottom of the filler plug
hole, you may need to add
some lubricant.
When the differential is cold, add enough lubricant to
raise the level to 3/8 inch (10 mm) below the filler
plug hole.
When the differential is at operating temperature
(warm), add enough lubricant to raise the level to the
bottom of the filler plug hole.
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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