yo R,
from my 96's owner's "guide".........
yo,
To shift between 4H and 4L:
With auto hubs;
Stop the vehicle and place the automatic
transmission into NEUTRAL or depress the
clutch on manual transmission vehicles. Push the
transfer case shift knob down (toward the
ground) and at the same time pull or push the
lever straight forward or rearward (depending
on the desired position, 4H or 4L) in order to
shift the transfer case. This shift should be in
one continuous motion without pausing in the N
(neutral) position. Pausing in the neutral position
can result in gear clash and difficult shifting. If,
while shifting between 4H and 4L, the transfer
case gets stuck in the N (neutral) position or is
difficult to shift into either 4H or 4L, it may be
necessary to let the vehicle roll slightly and/or
turn off the engine (particularly on vehicles
equipped with automatic transmissions)."
Key is..engine off w/auto..and roll...
Good luck!
Al