1994 GMC SIERRA Owners Manual

Driving Guidelines
Off-Road Driving with Your Four-wheel 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, solid surface.
Off-road driving can be great
fun. But it does have some definite 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 are
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-roading 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.
Loading Your Vehicle for Off-Road Driving
There are some important things to remember about how to load your
vehicle.
0 The heaviest things should be on the load floor and forward of your
rear axle. Put heavier items as far forward as you can.
Be sure the load is secured properly, so driving on the off-road terrain
doesn’t toss things around.
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You’ll find other important information in this manual. See “Vehicle
Loading,” “Luggage Carrier’’ and “Tires”
in the Index.
Traveling to Remote Areas
It makes sense to plan your trip, especially when going to a remote area.
Know the terrain and plan your route. You are much less likely to get bad
surprises. Get accurate
maps of trails and terrain. Try to learn of any
blocked or closed roads.
It’s
also a good idea to travel with at least one other vehicle. If something
happens
to one of them, the other can help quickly.
Does your vehicle have a winch? If
so, be sure to read the winch
instructions. In a remote area, a winch can be handy
if you get stuck. But
you’ll want to know how
to use it properly.
Getting Familiar with Off-Road Driving
It’s a good idea to practice in an area that’s safe and close to home before
you
go into the wilderness. Off-road driving does require some new and
different driving skills. Here’s what we mean.
Tune your senses to different kinds of signals. Your eyes, for example, need
to constantly sweep the terrain for unexpected obstacles. Your ears need to
listen for unusual tire
or engine sounds. With your arms, hands, feet, and
body you’ll need to respond to vibrations and vehicle bounce.
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Controlling your vehicle is the key to successful off-road driving. One of
the best ways to control your vehicle is to control your speed. Here are some
things to keep in mind. At higher speeds:
you approach things faster and you have less time to scan the\
terrain for
obstacles.
0 you have less time to react.
0 you have more vehicle bounce when you drive over obstacles.
you’ll need more distance for braking, especially since you’re on an
unpaved surface.
Scanning the Terrain
Off-road driving can take you over many different kinds of terrain. You
need to be familiar with the terrain and its many different features. Here are
some things to consider.
Surface Conditions. Off-roading can take you over hard-packed dirt,
gravel, rocks, grass, sand, mud, snow or ice. Each of these surfaces affects
the steering, acceleration, and braking of your vehicle in different ways.
Depending upon the kind of surface you are on, you may experience
slipping, sliding, wheel spinning, delayed acceleration, poor tra\
ction, and
longer braking distances.
Surface Obstacles. Unseen or hidden obstacles can be hazardous. A rock,
log, hole, rut, or bump can startle you if you’re not prepared for them. Often
these obstacles
are hidden by grass, bushes, snow or even the rise and fall of
the terrain itself. Here
are some things to consider:
Is the path ahead clear?
Will the surface texture change abruptly up ahead?
Does the travel take you uphill or downhill? (There’s more discussion\

Will you have to stop suddenly or change direction quickly?
of these subjects later.)
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When you drive over obstacles or rough terrain, keep a firm grip on the
steering wheel.
Ruts, troughs, or other surface features can jerk the wheel
out of your hands if you’re not prepared.
When
you drive over bumps, rocks, or other obstacles, your wheels can
leave
the ground. If this happens, even with one or two wheels, you can’t
control the vehicle
as well or at all.
Because you will be on an unpaved surface, it’s especially important
to
avoid sudden acceleration, sudden turns. or sudden braking.
In
a way, off-road driving requires a different kind of alertness from driving
on paved roads and highways. There are no road signs, posted speed limits
or signal lights.
You have to use your own good .judgment about what is safe
and what isn’t.
Drinking and driving can be very dangerous on any road. And this
is
certainly true for off-road driving. At the very time you need special
alertness and driving skills, your reflexes, perceptions and judgment can be
affected by even
a small amount of alcohol. You could have a serious - or
even
fatal - accident if you drink and drive or ride with a driver who has
been drinking. (See “Drunken Driving”
in the Index.)
Driving On Off-Road Hills
Off-road driving often takes you up, down, or across a hill. Driving safely
on hills requires good judgment and an understanding of what your vehicle
can and can’t do. There are some hills that simply can’t be driven, no matter
how well built the vehicle.
A CAUTION:
Many hills are simply too steep for any vehicle. If you drive up
them, you will stall.
If you drive down them, you can’t control
yorrr speed. If you drive across them, you will roll over. You
could be seriously injured or killed.
If you have any doubt about
the steepness, don’t drive the hill.
Approaching a Hill
When you approach a hill, you need to decide if it’s one of those hills that’s
just too steep to climb, descend, or cross. Steepness can be hard to judge.
Oil a very small hill, for example, there may be a smooth, constant incline
with only
a small change in elevation where you can easily see all the way
to
the top. On a large hill. the incline may get steeper as you near the top,
but
you may not see this because the crest of the hill is hidden by bushes,
grass, or shrubs.
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Here are some other things to consider as you approach a hill.
Is there a constant incline, or does the hill get sharply steeper in places'!
Is there good traction on the hillside, or will the surface cause tire
slipping?
Is there a straight path up or down the hill so you won't have to make
turning maneuvers?
Are there obstructions on the hill that can block your path (boulders,
trees, logs
or ruts)'?
What's beyond the hill? 1s there a cliff, an embankment, a drop-off, a
fence? Get out and walk the
hill if you don't know. It's the smart way
to find out.
Is the hill simply too rough? Steep hills often have ruts, gullies, troughs
and exposed rocks because they are more susceptible
to the effects of
erosion.
Driving Uphill
Once you decide you can safely drive up the hill, you need to take some
special steps.
Use a low gear and get a firm grip on the steering wheel.
Get a smooth start up the hill and try to maintain your speed. Don't use
more power than
you need, because you don"t want your wheels to start
spinning or sliding.
Try to drive straight up the hill if at all possible. If the path twists and
turns, you might want to find another route.
A CAUTION:
Tbrning or driving across steep hills can be dangerous, You
could lose traction, slide sideways, and possibly roll over.
You
could be seriously injured or killed. When driving up hills,
always
try to go straight up.
Ease up on your speed as you approach the top of the hill.
Attach a flag to the vehicle to make you more visible to approaching
traffic
on trails or hills.
Sound the horn as you approach the top of the hill to let opposing
traffic know you're there.
Use your headlights even during the day. They make you more visible
to oncoming traffic.
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Q: What should I do if my vehicle stalls, or is about to stall, and I
can’t make
it up the hill?
A:
0
a
a
a
If this happens, there are some things you should do, and there are
some things you must not do. First, here’s what you
slzould do:
Push the brake pedal to stop the vehicle and keep
it from rolling
backwards.
Also, apply the parking brake.
If your engine is still running, shift the transmission into reverse,
release the parking brake, and slowly back down
the hill in reverse.
If your engine has stopped running,
you’ll need to restart it. With the
brake pedal depressed and the parking brake still applied, shift the
transmission to
“P’ (Park) (or, shift to “N” (Neutral) if your vehicle has
a manual transmission) and restart the engine. Then, shift to reverse,
release the parking brake, and slowly back down the
hill as straight as
possible
in reverse.
As you are backing down the hill, put your left hand on the steering
wheel at the
12 o’clock position. This way, you’ll be able to tell if your
wheels are straight and maneuver as you back down. It’s best that you
back down the
hill with your wheels straight rather than in the left or
right direction. Turning the wheel too far to the left or right will
increase the possibility of
a rollover.
Here are some things
you mist nof do if you stall, or are about to stall,
when going up a
hill.
Never attempt to prevent a stall by shifting into “N” (Neutral) (or
depressing the clutch, if you have a manual transmission) to “rev-up”
the engine and regain forward momentum. This won’t work. Your
vehicle will roll backwards very quickly and you could go out of
control.
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Instead, apply the regular brake to stop the vehicle. Then apply the parking
brake. Shift into reverse, release the parking brake, and slowly back straight
down.
Never attempt to turn around if you are about to stall when going up a
hill. If the hill is steep enough to stall your vehicle, it’s steep enough to
cause
you to roll over if you turn around. If you can’t make it up the
hill, you must back straight down
the hill.
Q: Suppose, after stalling, I try to back down the hill and decide I just
can’t
do it. What should I do?
A: Set the parking brake, put your transmission in “P” (Park) (or the
manual transmission
in first gear) , and turn off the engine. Leave the
vehicle and
go get some help. Exit on the uphill side and stay clear of
the path the vehicle would take if it rolled downhill. Do not shift the
transfer case to
“N” (Neutral) when you leave the vehicle. Leave it in
some gear.
Driving Downhill
When off-roading takes you downhill, you’ll want to consider a number of
things:
Are there hidden surface obstacles? Ruts‘? Logs? Boulders?
What’s at the bottom of the hill? Is there a hidden creek bank or even a
river bottom with large rocks?
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If you decide you can go down a hill safely, then try to keep your vehicle
headed straight down, and use
a low gear. This way, engine drag can help
your brakes and they won’t have to do all the work. Descend slowly,
keeping your vehicle under control at
all times.
A CAUTION:
Heavy braking when going down a hill can cause your brakes to
overheat and fade. This could cause loss of control and a ser\
ious
accident. Apply the brakes lightly when descending a hill
and
use a low gear to keep vehicle speed under control.
Q: Are there some things I should not do when driving down a hill?
A: Yes! These are important because if you ignore them you could lose
control and have
a serious accident.
When driving downhill, avoid turns that take you across the incline of
the hill. A hill that’s not too steep to drive down may be too steep to
drive across. You could roll over if you don’t drive straight down.
0 Never go downhill with the transmission in “N” (Neutral) , or with the
clutch pedal depressed in a manual shift . This is called
“free-wheeling.” Your brakes will have to do
all the work and could
overheat and fade.
Avoid braking so hard that you lock the front wheels when going
downhill.
If your front wheels are locked, you can’t steer your vehicle.
If your wheels lock up during downhill braking, you
may feel the
vehicle starting
to slide sideways. To regain your direction, just ease off
the brakes and steer to keep the front of the vehicle pointing straight
downhill.
0: Am I likely to stall when going downhill?
A: It’s much more likely to happen going uphill. But if it happens going
downhill, here’s what to do.
0 Stop your vehicle by applying the regular brakes. Apply the parking
brake.
Shift to ‘bP’ (Park) (or to Neutral with the lnanual transmission) and,
while still braking, restart the engine.
0 Shift back to a low gear, release the parking brake, and drive straight
down.
0 If the engine won’t start, get out and get hclp.
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