GMC 2014 Sierra Owner's Manual page 392

1. Fill Plug
2. Drain Plug
To get an accurate reading, the
vehicle should be on a level
surface.
If the level is below the bottom of
the fill plug (1) hole, located on the
transfer case, some lubricant will
need to be added. Add enough
lubricant to raise the level to the
bottom of the fill plug (1) hole. Use
care not to overtighten the plug.
Refer to
to determine how often to
change the lubricant.
Refer to
determine what kind of lubricant
to use.
It is not necessary to regularly
check front axle fluid unless a leak
is suspected, or an unusual noise is
heard. A fluid loss could indicate a
problem. Have it inspected and
repaired.
To get an accurate reading, the
vehicle should be on a level
surface.
to
1. Fill Plug
2. Drain Plug