GMC 2004 Savana - Manual (Page 294)

Rear Axle
When to Check Lubricant
Refer to the Maintenance Schedule to determine how
often to check the lubricant. 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 you have the 1500 Series, the proper level is from 5/8
inch (15 mm) to 1 5/8 inch (40 mm) below the bottom
of the filler plug hole. The proper level for the 2500 and
3500 Series is from 0 to 1/4 (6 mm) below the bottom
of the filler plug hole. Add only enough fluid to reach the
proper level.
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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