Hummer 2007 H2 Owner's Manual page 439

How to Check Lubricant
A. Filler Plug
1. Remove the filler plug (A). The fluid level
should be just below the bottom of the
filler plug hole located on the transfer case.
To get an accurate reading, the vehicle should
be on a level surface.
B. Drain Plug
2. Add fluid if necessary.
Refer to the Maintenance Schedule to
determine what kind of lubricant to use.
See Recommended Fluids and Lubricants
on page 528.
3. Reinstall the filler plug. Use care not to
overtighten the filler plug.
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