1993 GMC SIERRA four wheel drive

Transfer Case
PO276
The transfer case shift lever is on the floor to the right of the driver. Use this
lever to shift into and
out of four-wheel drive. An indicator near the lever
shows
you the transfer case settings:
4L
2H
4H
K2224
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Featwes & Contmk
The front axle portion of the indicator diagram will light up when you shift into
four-wheel drive.
A slight delay between shifting and the indicator’s lighting is
normal.
If the indicator does not light up, or if the front axle light does not go
out after you shift out of four-wheel drive, have your dealer check your
system.
When your headlights or parking lights are on, rotate the dial\

to the right of
your headlight switch up
to brighten, or down to dim, your transfer case
indicator light.
Transfer Case Shift Positions
2H (High): This setting is for driving in most street and highway situations.
Your front axle is not engaged in two-wheel drive.
4H (High): This setting engages your front axle to help drive your vehicle.
Use
4H when you need extra traction, such as on wet or icy roads, or in
most
off -road situations.
N (Neutral): Shift to this setting only when your vehicle needs to be towed or
when using a power take
off.
4L (Low): This setting also engages your front axle to give you extra traction,
but should be used only for off-road or on extremely slippery surfaces.
You can shift from
2H to 4H or from 4H to 2H while the vehicle is moving.
Your front axle will engage faster
if you take your foot off of the accelerator
for a few seconds after you shift. In extremely cold weather it may be
necessary to stop or slow the vehicle to shift out of
2H.
To shift into or out of 4L or N (Neutral):
1. Slow the vehicle to a roll, about 3 mph (5 kmlh) and shift your
2. Shift the transfer case shift lever in one continuous motion.
transmission into neutral.
Don’t pause in
N (Neutral) as you shift the transfer case into 4L, or your
aears could clash.
Kernember that driving
in 4H or 4L may reduce fuel economy. Also, driving in
four-wheel drive on dry pavement could cause your tires to wea\
r faster and
make your transfer case harder
to shift.
Front Axle Locking Feature
The front axle locks and unlocks automatically when you shift the transfer
case.
A slight delay for the axle to lock or unlock is normal. If the outside
temperature is very hot, or the vehicle has been used under hard driving
conditions, there may be a slight delay for the axle to unlock.
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Whenever you are in four wheel-drive, the rear wheel anti-lock brake system
does not operate. The regular brake system operates normally. W\
hen you shift back into two-wheel drive, the anti-lock brake system will operate.
Windows
To open your manual windows, turn the hand crank on each door to raise or
lower your side door windows.
If you have the optional power windows, the controls are on each
of the side
doors.
The driver's door has a switch for the passenger windows as well. Your
power windows will work when the ignition has been turned to
ACC or Run.
Push the switch with the down pointing arrow to lower the window.
Push the switch with the up pointing arrow to raise the window.
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Your Driving and the Road
.
Here you’ll find information about driving different kinds of roads and in
varying weather conditions
. We’ve also included many other useful tips on
driving
.
Road Signs ........................................................................\
.................................... 4-3
Defensive Driving ........................................................................\
........................ 4-10
Drunken Driving ........................................................................\
........................... 4-11
Control of a Vehicle ........................................................................\
.................... 4-14
Braking ........................................................................\
...................................... 4-14
Steering ........................................................................\
.................................... 4-19
Steering in Emergencies ........................................................................\
......... 4-21
rassing ........................................................................\
..................................... 4-22
Loss of Control ........................................................................\
........................ 4-24
Off-Road Driving With Your Four-wheel Drive Vehicle
.................................... 4-25
Driving at Night
.............. w..i*&r,+v ........................................................................\
4-36
Driving in the Rain ........................................................................\
...................... 4-30
Driving in Fog, Mist and Haze ........................................................................\
.. 4-41
City Driving ........................................................................\
.................................. 4-42
Freeway Driving ........................................................................\
........................... 4-43
Driving a Long Distance ........................................................................\
............. 4-45
Hill and Mountain Roads ........................................................................\
............ 4-47
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c
AM41 501 6
As you brake, your computer keeps receiving updates on rear wheel spee\
d
and controls braking pressure accordingly.
CAUTION I
A
Anti-lock doesn’t change the time you need to get your foot up to I
the brake pedal. If you get too close to the vehicle in front of you,
you won’t have time
to apply your brakes if that vehicle suddenly
slows or stops. Always leave enough room up ahead to stop, even
though you have anti-lock brakes.
To Use Anti-Lock:
Use rear wheel anti-lock like regular brakes. You may feel the brakes vibrate,
or you may notice some noise outside your vehicle, but this is normal. Let
anti-lock work for you, but remember: Your front wheels can still stop rolling.
If that happens, release enough pressure on the brakes to get the wheels
rolling again
so that you can steer.
With the four-wheel drive option you won’t have anti-lock braking when you
shift into four-wheel drive. But you will have regular braking. When you shift
back into two-wheel drive, you will have anti-lock again.
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Your Drivm - and the Road.
Off-Road Recovery
You may find. sometime that your right wheels have dropped off the edge of
a road onto the shoulder while you're driving.
If the level of the shoulder is only slightly below the pavement, recovery
should be fairly easy. Ease
off the accelerator and then, if there is nothing in
the way, steer
'so that your vehicle straddles the edge of the pavement. You
can turn the steering wheel up to
1/4 turn until the right front tire contacts
the pavement edge. Then turn your steering wheel to go straight down the
roadway.
AM428003
If the shoulder appears to be about four inches (100 mm) or more below the
pavement, this difference can .cause problems.
If there is not enough room to
pull entirely onto the shoulder and stop, then follow the same proc\
edures. But
if the right front tire scrubs against the side of the pavement, do NOT steer
more sharply. With
too much steering angle, the vehicle may jump back onto
the road with
so much steering input that it crosses over .into the oncoming
traffic before you can bring
it back under control.
Instead, ease off again on the accelerator and steering input, \
straddle the
pavement once more, then
try again.
Passing
The driver of a vehicle about to pass another on a two-lane highway waits
for just the right moment, accelerates, moves around the vehicl\
e ahead, then
goes back into the right lane again.
A simple maneuver?
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may not realize the surface is slippery until your vehicle is skidding. Learn to
recognize warning clues-such as enough water, ice
or packed snow on the
road to make a “mirrored surface’’-and slow down when you have \
any
doubt.
Remember: the rear wheel anti-lock braking system (RWAL) helps\
avoid only
a rear braking skid. In a braking skid (where the front wheels are no longer
rolling), release enough pressure on the brakes to get the front wheels rolling
again. This restores steering control. Push the brake pedal dow\
n steadily
when you have to stop suddenly.
As long as the front wheels are rolling, you
will have steering control. Steer the way you want to go.
Off-Road Driving with Your FourcWheel
Drive Vehicle
This off-road guide is for vehicles that have four-wheel drive. Also, see
“Anti-lock Brakes” in the Index.
If your vehicle doesn’t have four-wheel drive,
you shouldn’t drive off-road unless you’re on a level, so\
lid surface.
Off-road driving can be great fun. But it does have some defi\
nite hazards.
The greatest
of these is the terrain itself.
“Off-roading” means you’ve left the great North American\
road system behind.
Traffic lanes aren’t marked. Curves aren’t banked. There a\
re no road signs.
Surfaces can be slippery, rough, uphill
or downhill. In short, you’ve gone right
back
to nature.
Off-road driving involves some new skills. And that’s why it’s very important
that you read this guide. You’ll find many driving tips and suggestions. These
will help make your off-road driving safer and more enjoyable. \
Before You Go Off-Roading
There are some things to do before you go out. For example, be sure to
have all necessary maintenance and service work done. Be sure \
you read all
the information about your four-wheel drive vehicle in this manual.
Is there
enough fuel?
Is the spare tire fully inflated? Are the fluid levels up where
they should be? What are the local laws that apply to off-roa\
ding where you’ll be driving?
If you don’t know, you should check with law enforcement people\

in the area. Will you be on someone’s private land?
If so, be sure to get the
necessary permission.
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Your Driving and the Road
drivers behind you are seeing your signal when they are not. It’s important to
check occasionally to be sure the trailer bulbs are still working.
Driving on Grades
Reduce speed and shift to a lower gear before you start down long or steep
downgrade.
If you don’t shift down, you might have to use your brakes so
much that they would get hot and no longer work well.
On a long uphill grade, shift down and reduce your speed to
45 mph (70
kmlh) or less to reduce the possibility of engine and transmission overheating.
IT you have an automatic transmission, you should use D (or, as you need to,
a lower gear) when towing a trailer. Operating your vehicle i\
n
D when towing
a trailer will minimize heat buildup and extend the life of your transmission.
Or, if you have a manual transmission with fifth gear and you are towing a
trailer, it’s better not to use fifth gear. Just drive in fourth gear
(or, as you
need to, a lower gear).
Parking on Hills
You really should not park your vehicle, with a trailer attached, \
on a hill. If
something goes wrong, your rig could start to move. People can\
be injured
and both your vehicle and the trailer can be damaged.
But
if you ever have to park your rig on a hill, here’s how to do it:
1. Apply your regular brakes, but don’t shift into P (Park) yet, or into gear
2. Have someone place chocks under the trailer wheels.
for a manual transmission.
3. When the wheel chocks are
in place, release the regular brakes until the
chocks absorb the load.
4. Reapply the regular brakes. Then apply your parking brake, and \
then
5. If you have a four-wheel-drive vehicle, be sure the transfer case is in a
6. Release the regular brakes.
shift
to
P (Park), or R (Reverse) for a manual transmission.
drive gear-not in
N (Neutral).
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