GMC 2009 Savana - Manual (Page 287)

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 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’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.
What to Use
Refer to the Maintenance Schedule to determine what
kind of lubricant to use. See Recommended Fluids
and Lubricants on page 6-14.
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