GMC Yukon - Four-Wheel Drive

2500 Series
To get an accurate reading, the vehicle should be on a
level surface.
.
For all 4.8L, 5.3L 1500 series and all 6.2L all wheel
drive 1500 series luxury model applications , the
proper level is from 0.04 inch to 0.75 inch (1.0 mm
to 19.0 mm) below the bottom of the filler plug hole,
located on the rear axle. Add only enough fluid to
reach the proper level.
.
For all 6.0L 1500 series and all 6.2L non‐all wheel
drive 1500 series luxury model applications, the
proper level is from 0.6 inch to 1.6 inches (15 mm
to 40 mm) below the bottom of the filler plug hole,
located on the rear axle. Add only enough fluid to
reach the proper level.
.
The proper fill level for the 2500 series is from 0 to
1/2 inch (0 to 13 mm) below the bottom of the filler
plug hole, located at the front of the axle. Add only
enough fluid to reach the proper level.
Four-Wheel Drive
Lubricant checks in this section also apply to these
vehicles. There are two additional systems that need
lubrication.
Transfer Case
When to Check Lubricant
It is not necessary to regularly check transfer case 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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