drain plug GMC YUKON 2006 Owner's Manual

Also, if a vehicle has just been driven before checking the
uid level, it may appear lower than normal because uid
has traveled out along the axle tubes and has not drained
back to the sump area. Therefore, a reading taken
ve minutes after the vehicle has been driven will appear
to have a lower uid level than a vehicle that has been
stationary for an hour or two. Remember that the rear
axle assembly must be supported to get a true reading.
How to Check Lubricant
To get an accurate reading, the vehicle should be
on a level surface.
The proper level for the 1500 Series is from
5/8 inch to 1 5/8 inch (15 mm to 40 mm) below
the bottom of the ller plug hole.
The proper level for the 2500 Series is from
0 to 1/2 inch (0 to 13 mm) below the bottom of
the ller plug hole.
Add only enough uid to reach the proper level.
What to Use
To determine what kind of lubricant to use, see
Recommended Fluids and Lubricants on page 6-13.
1500 Series shown, 2500 similar
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