lock CHEVROLET SUBURBAN 1997 Repair Manual

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 the
rear wheels. The
anti-lock system can change the brake 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.
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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
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.
Variable Effort 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.
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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.
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 one-quarter turn until the
right front tire contacts the pavement edge. Then
turn your
steering wheel to go straight down the roadway.
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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.
Driving Guidelines
This multipurpose passenger vehicle is defied as a utility
vehicle in Consumer Information Regulations issued by
the National Highway Trafpc Safety Administration
(NHTSA) of the United States Department of
Transportation. Utility vehicles have higher ground
clearance and a narrower track to make them capable of
performing in a wide variety of off-road applications.
Specific design characteristics give them a higher center of
gravity than ordinary cars.
An advantage of the higher
ground clearance is a better view of the road allowing you
to anticipate problems. They are not designed for
cornering at the same speeds as conventional
two-wheel-drive vehicles any more than low-slung
sports
cars are designed to perform satisfactorily under off-road conditions.
If at
all possible, avoid sharp turns or abrupt
maneuvers. As with other vehicles of this type, failure to
operate
this vehicle correctly may result in loss of control
or vehicle rollover.
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.
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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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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.
0 Is there a constant incline, or does the hill get sharply
steeper in places?
0 Is there good traction on the hillside, or will the
Is there a straight path up or down the hill so you
surface cause tire slipping?
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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Qt 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
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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.
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) 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).
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.
Never attempt to prevent a stall by shifting into
NEUTRAL (N) 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.
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--
What’s the worst time for this? “Wet ice.” Very cold
snow or ice can be slick and hard to drive on. But wet
ice can be even more trouble because it may offer the
least traction of all. You can get wet ice
when it’s about
freezing
(32°F; 0°C) and freezing rain begins to fall.
Try to avoid driving on
wet ice until salt and sand crews
can get there. Whatever the condition
-- smooth ice, packed, blowing
or loose snow
-- drive with caution.
Accelerate gently. Try not to break the fragile traction. If
you accelerate too fast, the drive wheels will spin and
polish the surface under the tires even more.
Your anti-lock brakes improve your vehicle’s stability
when you make a hard stop on a slippery road. Even
though
you have an anti-lock braking system, you’ll
want to begin stopping sooner than you would on dry
pavement. See “Anti-Lock” in
the Index.
Allow greater following distance on any
slippery road.
Watch for slippery spots. The road might be fine
until
you hit a spot that’s covered with ice. On an
otherwise clear road, ice patches may appear in
shaded areas where the
sun can’t reach: around
clumps of trees, behind buildings or under bridges.
Sometimes the surface
of a curve or an overpass may
remain icy when the surrounding roads are clear.
If
you see a patch of ice ahead of you, brake before you
are on
it. Try not to brake while you’re actually on
the ice, and avoid sudden steering maneuvers.
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You can run the engine to keep warm, but be careful.
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Snow can trap exhaust gases under your vehicle.
This can cause deadly
CO (carbon monoxide) gas
to get inside.
CO could overcome you and kill
you. You can’t see it or smell it,
so you might not
know it is in your vehicle. Clear away snow from
around the base of your vehicle, especially any
that is blocking your exhaust pipe. And check
around again from time to time to be sure snow
doesn’t collect there.
Open
a window just a little on the side of the
vehicle that’s away from the wind. This will help
keep
CO out.
Run your engine only as long as you must. This saves
fuel. When you run the engine, make it go a little faster
than just idle. That is, push the accelerator slightly. This
uses less fuel for the heat that you get and it keeps
the
battery (or batteries) charged. You will need a
well-charged battery (or batteries) to restart the vehicle,
and possibly for signaling later on with your headlamps.
Let the heater
run for awhile.
If you have a diesel engine,
you may have to run it at a
higher speed to get enough heat. Then, shut the engine
off and close the window almost all the way to preserve
the heat. Start the engine again and repeat this only
when you
feel really uncomfortable from the cold. But
do it as little as possible. Preserve the fuel as long as you
can. To help keep warm, you can get out
of the vehicle
and do some fairly vigorous exercises every half hour or
so until help comes.
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Power Winches
If you wish to use a power winch on your vehicle, only
use it when your vehicle is stationary or anchored.
NOTICE:
Using a power winch with the transmission in
gear may damage the transmission. When
operating a power winch, always leave the
transmission in
NEUTRAL (N).
Use the regular brakes, set the parking brake, or block
the wheels to keep your vehicle from rolling.
Power Take-Off (PTO)
I NOTICE:
If you have a PTO that will exceed 35 hp installed
on your vehicle, it could damage the transfer case
or transmission. When having a PTO installed on
your vehicle, make sure that it will not exceed
35 hp.
Before using a PTO, refer to the manufacturer’s or
installer’s instructions.
NOTICE:
Using a PTO while operating in one place before
the vehicle has reached normal operating
temperature can damage the transfer case or
transmission.
If you will be using the PTO while
operating in one place, drive and warm up the
vehicle before using the PTO.
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