wheel GMC SIERRA 1994 Owner's Manual

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 an advanced electronic braking system that can help you
keep it under control.
When you start your vehicle and begin to drive away, you may hear
a
momentary motor or clicking noise. The ABS motor comes on momentarily
when
the vehicle reaches 8 mph (I 2 km/h). And you may even notice that
your brake pedal moves a little while this is going on. This
is the ABS
system testing itself.
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 the rear wheels are slowing down.
IT one of the rear
wheels is about to stop rolling, the computer will work
the brakes at the rear
wheels.
It is programmed to make the most of available tire and road
conditions.
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I- .,
As you brake, your computer keeps receiving updates on rear 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. 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.
Braking in Emergencies
At some time, nearly every driver gets into a situation that requires hard
braking.
You have the rear-wheel anti-lock braking system.
Your front wheels can
stop rolling
when you brake very hard. Once they do, the vehicle can't
respond
to your steering. Momentum will carry it in whatever direction it
was headed when the front wheels stopped rolling. That could be off the
road, into the very thing you were trying to avoid, or into traffic.
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So, use a “squeeze” braking technique. This will give you maximum
braking while maintaining steering control. You do this by pushing on the
brake pedal with steadily increasing pressure. When you do,
it will help
maintain steering control. 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.
Steering lips
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 apply
the brakes. Both control systems
- steering and braking - have to do their
work where the tires meet the road. Adding the hard braking can demand
too much at those places.
You can lose control.
The same thing can happen
if you’re steering through a sharp curve and you
suddenly accelerate. Those
two control systems - steering and acceleration
- can overwhelm those places where the tires meet the road and make you
lose control.
What should you do
if this ever happens? Ease up on the brake or
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.
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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.
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 emergen.cies like these. First apply
your brakes, but not enough to lock your front wheels. 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 quicltly, and just
as quickly
straighten
the wheel once you have avoided the object.
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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
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.
1. Edge of Road
Surface
2. Slow Down
3. Left Approx.
Quarter Turn
4. Recover
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 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:
0 “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.
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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: 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 down
steadily when you have
to stop suddenly. As long as the front wheels are
rolling, you
will have steering control.
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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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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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