Four-Wheeldrive - GMC 1994 Yukon Owner's Manual

If you have four-wheel drive and your transfer case is in
" N '
(Neutral),
your vehicle will be free to roll, even if your shift lever is in
" P '
(Park). So,
be sure the transfer case is in a drive gear
-
not in "N" (Neutral). Follow
the proper steps to be sure your vehicle won't move. See "Shifting Into 'P'
(Park)" in the Index.
If you're pulling a trailer, see "Towing a Trailer" in the Index.
Four Wheel Drive
If your vehicle has four-wheel drive, you can send your engine's driving
power to all four wheels for extra traction. To get the most satisfaction out
of four-wheel drive, you must be familiar with it's operation. Read the part
that follows before using four-wheel drive. You should use 2H
for most
normal driving conditions.
Rear-wheel antilock brakes do not work when you shift into four-wheel
drive. Your rcgular brakes will still work. When you shift back into
two-wheel drive, your rear-wheel antilock brakes will take over again.
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