Transfer Case - GMC 2002 Yukon Denali Owner's Manual

What to Use
Refer to the Maintenance Schedule to determine what
kind of lubricant to use. See "Recommended Fluids
and Lubricants" in the Index.
All Wheel Drive
-
Lubricant checks in this section also apply to these
vehicles. However, there are two additional systems
that need lubrication.

Transfer Case

When to Check Lubricant
Refer to the Maintenance Schedule to determine how
often to check the lubricant. See "Periodic Maintenance
Inspections" in the Index.
6-24
How to Check Lubricant
Automatic Transfer Case
(A) Filler Plug (B) Drain Plug
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'll need to add some lubricant. Add enough lubricant
to raise the level to the bottom of the filler plug hole.
Use care not to overtighten the plug.