GMC 2007 Envoy - Manual (Page 428)

Rear Axle
When to Check Lubricant
It is not necessary to regularly check rear 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.
The proper level is from 0 to 3/8 inch (0 to 10 mm)
below the bottom of the filler plug hole, located
on the rear axle.
What to Use
To determine what kind of lubricant to use, see
Recommended Fluids and Lubricants on page 517.
Four-Wheel Drive
Transfer Case
When to Check Lubricant
It is not necessary to regularly check 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.
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