wheel GMC SIERRA 1998 Owner's Guide

If your engine ever stops while you’re driving, brake
normally but don’t pump your brakes.
If you do, the
pedal may get harder to push down. If your engine
stops, you will still have some power brake assist. But
you will use it when you brake. Once the power assist is
used up, it may take longer to stop and the brake pedal
will be harder to push.
Anti-Lock Brakes (ABS)
Your vehicle has anti-lock brakes (ABS). ABS is an
advanced electronic braking system that will help
prevent a braking skid.
When you start your engine and begin
to drive away,
your anti-lock brake system will check itself. You may
hear
a momentary motor or clicking noise while this
test is going on. This is normal.
(@!
ANTI -
If there’s a problem with
the anti-lock brake system,
this warning light will stay
on. See “Anti-Lock Brake
System Warning Light”
in
I LOCK I the Index. Here’s how
anti-lock works. Let’s say the road
is wet.
You’re driving safely. Suddenly an animal jumps out
in
front of you.
You slam
on the brakes. Here’s what happens with ABS.
A computer senses that wheels are slowing down. If one
of the wheels is about to stop rolling, the computer will
separately work the brakes at each front wheel and at
both rear wheels.
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The anti-lock system can change the brlzke pressure faster
than any driver could. The computer is programmed
to
make the most of available tire and road conditions.
You can steer around the obstacle while braking hard.
As you brake, your computer keeps receiving updates on
wheel speed and controls braking pressure accordingly. Remember: Anti-lock doesn’t change the
time you need
to get your foot
up to the brake pedal or always decrease
stopping distance.
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.
Using Anti-Lock
Don’t pump the brakes. Just hold the brake pedal down
firmly and let anti-lock work for you.
You may feel the
brakes vibrate, or you may notice some noise, but this is
normal. On vehicles
with four-wheel drive, your
anti-lock brakes work at all times
-- whether you are in
two-wheel drive or four-wheel drive.
Braking in Emergencies
With anti-lock, you can steer and brake at the same
time. In many emergencies, steering can help you more
than even the very best braking.
Steering
Power Steering
If you lose power steering assist because the engine
stops
or the system is not functioning, you can steer but
it will take much more effort.
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Speed Sensitive Steering
This system varies the amount of steering effort
proportionate
to your vehicle speed. Steering is easier at
lower speeds for maneuvering and parking ease.
As your
vehicle speed increases,
the steering effort also
increases.
At highway speeds, the amount of steering
effort is increased for vehicle control and stability.
Steering Tips
Driving on Curves
It’s important to take curves at a reasonable speed.
A lot of the “driver lost control” accidents mentioned on
the news happen on curves. Here’s why:
Experienced driver or beginner, each
of us is subject to
the same laws of physics when driving on curves. The
traction of the tires against the road surface makes
it
possible for the vehicle to change its path when you turn
the front wheels.
If there’s no traction, inertia will keep
the vehicle going
in the same direction. If you’ve ever
tried
to steer a vehicle on wet ice, you‘ll understand this.
The traction
you can get in a curve depends on the
condition of your tires and the road surface, the angle at which the curve
is banked, and your speed. While you’re in
a curve, speed is the one factor you can control. Suppose you’re
steering through a sharp curve.
Then you suddenly accelerate. Both control
systems
-- steering and acceleration -- have to do their
work where the tires meet the road. Adding the sudden
acceleration can demand too much
of those places. You
can lose control.
What should
you do if this ever happens? Ease up on the
accelerator pedal, steer the vehicle the way
you want it
to go, and slow down.
Speed
limit signs near curves warn that you should
adjust your speed.
Of course, the posted speeds are
based on good weather and road conditions. Under less
favorable conditions you’ll want to go slower.
If you need to reduce your speed as you approach a
curve, do
it before you enter the curve, while your front
wheels are straight ahead.
Try to adjust your speed
so you can “drive” through the
curve. Maintain a reasonable, steady speed. Wait to
accelerate
until you are out of the curve, and then
accelerate gently into the straightaway.
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Steering in Emergencies
There are times when steering can be more effective
than braking. For example, you come over a hill and
find a truck stopped in your lane, or
a car suddenly pulls
out from nowhere, or
a child darts out from between
parked cars and stops right in front
of you. You can
avoid these problems by braking
-- if you can stop in
time. But sometimes you can’t; there isn’t room.
That’s
the time for evasive action -- steering around
the problem.
Your vehicle can perform very well
in emergencies like
these. First apply your brakes. (See “Braking in
Emergencies’’ earlier in this section.)
It is better to
remove as much speed as you can from a possible
collision. Then steer around the problem, to the left or
right depending on the space available. An
emergency like this requires close attention
and a
quick decision. If you are holding the steering wheel at
the recommended
9 and 3 o’clock positions, you can
turn it
a full 180 degrees very quickly without removing
either hand. But
you have to act fast, steer quickly, and
just as quickly straighten the wheel once you have
avoided
the object.
The fact that such emergency situations are always
possible is a good reason to practice defensive driving at
all times and wear safety belts properly.
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Off-Road Recovery Passing
You may find 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 one-quarter turn
until the right front tire contacts the pavement edge.
Then
turn your steering wheel to go straight down
the roadway. The driver
of a vehicle about to pass another on a
two-lane highway waits
for just the right moment,
accelerates, lnoves around the vehicle ahead, then goes
back into the right
lane again. A simple maneuver‘?
Not necessarily! Passing another vehicle on a two-lane
highway is
a potentially dangerous move, since the
passing vehicle occupies the same lane as oncoming
traffic for several seconds.
A miscalculation, an error in
judgment, or a brief surrender to frustration or anger can
suddenly
put the passing driver face to face with the
worst of all traffic accidents -- the head-on collision.
So here are some tips for passing:
“Drive ahead.” Look down the road, to the sides and to
crossroads for situations that might affect your passing
patterns.
If you have any doubt whatsoever about
making a successful pass, wait for a better time.
Watch for traff‘ic signs, pavernent rnarkings and lines.
If you can see a sign up ahead that might indicate a
turn or an intersection, delay your pass. A broken
center line usually indicates it‘s all right to pass
(providing the road ahead is clear). Never cross
a solid
line on
YOLII- side of the lane or a double solid line,
even if the road seems empty of approaching traffic.
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Loss of Control
Let’s review what driving experts say about what
happens when the three control systems (brakes, steering
and acceleration) don’t have enough friction where
the
tires meet the road to do what the driver has asked.
In any emergency, don’t give up. Keep trying to steer and
constantly seek an escape route or area of less danger.
Skidding
In a skid, a driver can lose control of the vehicle. Defensive
drivers avoid most skids by taking reasonable care suited
to
existing conditions, and by not “overdriving” those
conditions. But skids are always possible.
The three types of skids correspond
to your vehicle’s
three control systems. In the braking skid, your wheels
aren’t rolling. In the steering or cornering skid,
too
much speed or steering in a curve causes tires to slip and
lose cornering force. And
in the acceleration skid, too
much throttle causes the driving wheels to spin.
A cornering skid and an acceleration skid are best
handled by easing your foot off the accelerator pedal. If
your vehicle starts
to slide, ease your foot off the
accelerator pedal and quickly steer the way you want the
vehicle
to go. If you start steering quickly enough, your
vehicle may straighten out. Always be ready for
a
second skid if it occurs.
Of course, traction
is reduced when water, snow, ice.
gravel or other material
is on the road. For safety, you’ll
want to slow down and adjust your driving to these
conditions.
It is important to slow down on slippery
surfaces because stopping distance will be longer and
vehicle control more limited.
While driving on a surface
with reduced traction, try
your best to avoid sudden steering, acceleration or
braking (including engine braking
by shifting to a lower
gear). Any sudden changes could cause the tires
to slide.
You 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:
Any anti-lock brake system (ABS) helps
avoid only the braking skid.
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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. 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
firel‘?
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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Environmental Concerns
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Cargo on the load floor piled higher man
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. Off-road
driving can provide wholesome and satisfying
recreation. However,
it also raises environmental
concerns.
GM recognizes these concerns and urges
evesy 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
j.
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.
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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$ace Conditions. Off-roading can take you over
hard-packed dirt, gravel, rocks, grass, sand, mud, snow or
ice. Each
of these surfaces affects the steering, acceleration
and braking of your vehicle in different ways. Depending
upon the kind of surface
you are on, you may experience
slipping, sliding, wheel spinning, delayed acceleration,
poor traction and longer braking distances.
Su$ace 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 of these subjects later.)
Will you have to stop suddenly or change
direction quickly? 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.
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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.
l A C * UYON:
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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.
Turning 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.
1 A CAUTION:
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.
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