1993 CHEVROLET SUBURBAN traction control

CAUTION
I Cruise Control can be dangerous where you can’t drive safely\
at
I A a steady speed. So, don’t use your Cruise Control on winding
roads
or in heavy traffic.
Cruise Control can be dangerous on slippery roads. On such
roads, fast changes in tire traction can cause needless wheel
spinning, and you could lose control. Don’t
use Cruise Control
on slipPery roads.
To Set Cruise Control
A
K2248
Move the Cruise switch to ON.
I CAUTION
If you leave your Cruise Control switch on when you’re not using I
want to. You could be startled and even lose control. Keep the
Cruise Control switch OFF until vou want to use it. I
A Cruise, you might hit a button and go into Cruise when you don’t
I
Get up to the speed you want.
Push in the set button at the end of the lever and release \
it.
Take your foot off the accelerator pedal.
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Your Driving and the Road
Rear Drum Brakes
Your rear drum brakes don’t have the wear indicators, but if you ever hear a
rear brake rubbing noise, have the rear brake lining inspected.\

Also, the rear
brake drums should be removed and inspected each time the tire\
s are removed for rotation or changing. When you have the front brak\
es replaced,
have the rear brakes inspected, too.
Brake linings should always be replaced as complete axle sets. \
Brake Pedal Travel
See your dealer if the brake pedal does not return to normal height, or if
there is a rapid increase in pedal travel. This could be a sign of brake
trouble.
Brake Adjustment
Every time you make a brake stop, your disc brakes adjust for\
wear. If your
brake pedal goes down farther than normal, your rear drum brak\
es may need
adjustment. Adjust them by backing up and firmly applying the brakes a few
times.
Braking In Emergencies
Use your anti-lock braking system when you need to. With anti-lock, you \
can
steer and brake at the same time. In many emergencies, steerin\
g 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
fails to function, you can steer but it will take much more effort.
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 n\
ews 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.
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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. Those two control systems-steering and acceleration-ca\
n
overwhelm those places where the tires meet the road and make \
you lose
control.
What should you do if this ever happens? Let up on the accel\
erator peaal,
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.
When you drive into
a curve at night, it’s harder to see the road ahead of
you because it bends away from the straight beams
of your lights. This is
one
good reason to drive slower.
Steering in Emergencies
There are times when steering can be more effective than braki\
ng. 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 proble\
m.
Your vehicle can perform very well in emergencies like these. First \
apply your
brakes.
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
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Loss of Control
Let’s review what driving experts say about what happens whe\
n the three
control systems (brakes, steering and acceleration) don’t ha\
ve 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 d\
rivers avoid
most skids by taking reasonable care suited
to existing conditions, and by not
“overdriving” those conditions. But skids are always possib\
le.
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 (as when you turn
a corner on a wet, snow-
or ice-covered road), ease your foot off the
accelerator pedal as soon as you feel the vehicle start
to slide. Quickly steer
the way you want the vehicle
to go. If you start steering quickly enough, your
vehicle will straighten out. As it does, straighten the front wheels.
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 limit\
ed.
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 t\
o 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 braking system (ABS) helps avoid only the braking
skid. Steer the way you want
to go.
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Your Driving and the Road
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, hand\
s, feet, and
body you’ll need to respond
to vibrations and vehicle bounce.
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.
you have less time to react.
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.
A
When you’re driving off road, bouncing and quick changes in I
direction can easily throw you out of position. This could cause you
to lose control and crash.
So, whether you are driving on or off the
road, you and your passengers should wear your safety belts.
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 traction, 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?
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AM440002
I Getting out on the downhill (low) side of a vehicle stopped across an
- , incline is dangerous. If the vehicle rolls over, you could be crushed
or killed. Always get out on the uphill (high) side of the vehicle and
stay well clear of the rollover path. F
Driving In Mud, Sand, Snow, Or Ice
When you drive in mud, snow or sand, your wheels won’t get\
good traction.
You can’t accelerate as quickly, turning is more difficult, and \
you’ll need
longer braking distances.
It’s best to use a low gear when you’re in mud-the deeper the \
mud, the
lower the gear. In really deep mud, the idea is
to keep your vehicle moving
so you don’t get stuck.
When you drive on sand, you’ll sense a change in wheel tra\
ction. But
it will
depend upon how loosely packed the sand is. On loosely packed \
sand (as
on beaches or sand dunes) your tires will tend to sink into the\
sand. This
has an effect on steering, accelerating, and braking. You may want to reduce
the air pressure
in your tires slightly when driving on sand. This will improve
traction.
Hard packed snow and ice offer the worst tire traction. On these surfaces, it’s
very easy to lose control. On wet ice, for example, the tract\
ion is
so poor
that you will have difficulty accelerating. And
if you do get moving, poor
steering and difficult braking can cause you to slide out
of control.
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Service & Appearance Care
If you ever replace your tires with those not having a TPC Spec number,
make sure they are the same size, load range, speed rating an\
d construction
type (bias, bias-belted or radial) as your original tires.
I CAUTION
A
Mixing tires could cause you to lose control while driving. If you mix
tires
of different sizes or types (radial and bias-belted tires) the
vehicle may not handle properly, and you could have a crash. Be
sure
to use the same size and type tires on all wheels.
I
Uniform Tire Quarity Grading
The following information relates to the system developed by the United
States National Highway Traffic Safety Administration which grade\
s tires by
treadwear, traction and temperature performance. (This applies o\
nly to
vehicles sold in the United States.)
Treadwear
The treadwear grade is a comparative rating based on the wear \
rate of the
tire when tested under controlled conditions on a specified government test
course.
For example, a tire graded 150 would wear one and a half (1 1/2)
times as well on the government course as a tire graded 100. The relative
performance
of tires depends upon the actual conditions of their use,
however, and may depart significantly from the norm due to var\
iations
in
driving habits, service practices and differences in road characteristics and
climate.
Traction-A, B, C
The traction grades, from highest to lowesr are: A, 8, and C. They represent
the tire’s ability to stop on wet pavement as measured under controlled
conditions on specified government test surfaces of asphalt and concrete. A
tire marked
C may have poor traction performance.
Warning: The traction grade assigned to this tire is based on braking
(straight-ahead) traction tests and does not include cornering \
(turning) traction.
Temperature-A, B, C
The temperature grades are A (the highest), B, and C, representing the tire’s
resistance to the generation
of heat and its ability to dissipate heat when
tested under controlled conditions on a specified indoor laborat\
ory test wheel.
Sustained high temperature can cause the material
of the tire to degenerate
and reduce tire life, and excessive temperature can lead to sudden tire
failure. The grade
C corresponds to a level of performance which all
passenger car tires must meet under the Federal Motor Vehicle \
Safety
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