GM Chevrolet Avalanche - Manual (Page 385)

How to Check Lubricant
1. Remove the filler plug.
2. Add new fluid until the level is 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.
Refer to the Maintenance Schedule to determine
what kind of lubricant to use. See Recommended
Fluids and Lubricants on page 6-13.
3. Reinstall the filler plug. Use care not to overtighten
the filler plug.
Front Axle
When to Check and Change Lubricant
It is not necessary to regularly check front axle fluid
unless you suspect there is a leak or you hear an
unusual noise. A fluid loss could indicate a problem.
Have it inspected and repaired.
How to Check Lubricant
To get an accurate reading, the vehicle should be on a
level surface.
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