1997 GMC SIERRA Owners Manual

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. Check to make sure all
underbody shields
(if so equipped) are properly
attached. 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.
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.
Cargo on the load floor piled higher than
the seatbacks can be thrown forward
during a sudden stop. You or your
passengers could be injured. Keep cargo
below the top of the seatbacks.
Unsecured cargo on the load floor can be
tossed about when driving over rough
terrain. You or your passengers can
be struck
by flying objects. Secure the
cargo properly.
Heavy loads on the roof raise the vehicle’s
center of gravity, making it more likely to
roll over. You can be seriously or fatally
injured
if the vehicle rolls over. Put heavy
loads inside the cargo area, not on the roof.
Keep cargo in the cargo area as far forward
and low
as possible.
You’ll find other important information
in this manual.
See “Vehicle Loading,” “Luggage Carrier” and “Tires”
in the Index.
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Environmental Concerns
Off-road driving can provide wholesome and satisfying
recreation. However, it also raises environmental
concerns.
GM recognizes these concerns and urges
every off-roader to follow these basic rules for
protecting the environment:
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Always use established trails, roads and areas that
have been specially set aside for public off-road
recreational driving; obey all posted regulations.
Avoid any driving practice that could damage the
environment
-- shrubs, flowers, trees, grasses -- or
disturb wildlife (this includes wheel-spinning,
breaking down trees or unnecessary driving through
streams
or over soft ground).
Always carry a litter bag
. . . make sure all refuse is
removed from any campsite before leaving.
Take extreme care with open fires (where permitted),
camp stoves and lanterns.
Never park your vehicle over dry grass or other
combustible materials that could catch fire from the
heat of the vehicle’s exhaust system.
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:
0 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
you’ll need more distance for braking, especially
over
obstacles.
since you’re on an unpaved surface.
When you’re driving off-road, bouncing and
quick changes in direction can
-1 easily throw you
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.
Su@ace 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 traction and longer
braking distances.
Surjiuce Obstucles. 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:
out of position. This could cause you to lose
control and crash.
So, whether you’re driving on
or off the road, you and your passengers should
wear safety belts.
0 Does the travel take you uphill or downhill? (There’s
0 Is the path ahead clear?
0 Will the surface texture change abruptly up ahead?
L more discussion of these subjects later.)
0 Will you have to stop suddenly or change
direction quickly?
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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.
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.
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.
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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 your 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.
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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. On 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.
Here are some other things to consider as you approach a hill\
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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?
Is 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.
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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:
lhrning 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.
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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 headlamps even during the day. They make
you more visible
to oncoming traffic.
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Driving to the top (crest) of a hill at full speed can
cause an accident. There could be a drop-off,
embankment,
cliff, or even another vehicle. You
could be seriously injured or killed.
As you near
the top
of a hill, slow down and stay alert.
@ What should I do if my vehicle stalls, or is about
A: If this happens, there are some things you should
to stall, and I can’t make it up the hill?
do, and there are some things you must not do.
First, here’s what you
should do:
Push the brake pedal to stop the vehicle and keep it
from rolling backwards. Also, apply
the parking brake.
0 If your engine is still running, shift the transmission
to REVERSE
(R), release the parking brake, and
slowly back down the
hill in REVERSE (R).
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
PARK (P) (or, shift to NEUTRAL (N) if your
vehicle has a manual transmission) and restart
the
engine. Then, shift to REVERSE (R), release the
parking brake,
and slowly back down the hill as
straight as possible in REVERSE
(R).
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0 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
must not do if you stall, or are
about to stall, when going up a hill.
0 Never attempt to prevent a stall by shifting into
NEUTRAL
(N) (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.
Instead, apply the regular brake to stop the
vehicle. Then apply
the parking brake. Shift to
REVERSE (R), release the parking brake, and
slowly back straight down.
0 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.
@ 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
PARK (P) (or the manual transmission in FIRST (1))
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 NEUTRAL (N)
when you leave the vehicle. Leave it in I ne gel
Shifting the transfer case to NEUTR
I (N) can
cause your vehicle to roll even if the transmission
is in PARK (P) (or, if you have the manual
transmission, even if you’re in gear). This is
because the
NEUTRAL (N) position on the
transfer case overrides the transmission.
If you
are going to leave your vehicle, set the parking
brake and shift the transmission to
PARK (P)
(or, put your manual transmission in FIRST (1)).
But do not shift the transfer case to the
NEUTRAL
(N) position. Leave the transfer case
in the
2 Wheel, 4 High or 4 Low position.
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Driving Downhill
When off-roading takes you downhill, you 11 want to
consider
a number of things:
How steep is the downhill? Will I be able to maintain
What’s the surface like? Smooth? Rough? Slippery?
Are there hidden surface obstacles? Ruts? Logs?
What’s at the bottom of the hill? Is there a hidden
vehicle control?
Hard-packed dirt? Gravel?
Boulders?
creek bank or even a river bottom with large rocks?
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.
I a CAUTIO, .:
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Heavy braking when going down a hill can cause
your brakes to overheat and fade. This could
cause loss of control and
a serious accident.
Apply the brakes lightly when descending a
hill and use a low gear to keep vehicle speed
under control.
&: Are there some things I should not do when
A: Yes! These are important because if you ignore them
driving down a hill?
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.
Never
go downhill with the transmission in
NEUTRAL
(N), 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.
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