1998 GMC SIERRA lock

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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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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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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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. 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.
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. you have less time to react.
0 you have more vehicle bounce when you drive
over obstacles.
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.
0 you’ll need more distance for braking, especially
since you’re on an unpaved surface.
When you’re driving off-road, bouncing and
quick changes in direction can easily throw you
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.
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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.
I a CAUTION:
Many hills are simply too steep for any vehicle. If
you drive up them, you will stall. If you drive
1 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.
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 tojudge. 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.
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What should I do if my vehicle stalls, or is about
to stall, and I can’t make it up the hill?
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
should do:
0 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).
0 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).
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.
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.
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