2003 CHEVROLET IMPALA brakes

Braking
Braking action involvesperception timeandreaction
time.
First, you have to decide to push on the brake pedal.
That'sperception time.Then you have to bring up your
foot and do it. That'sreaction time.
Averagereaction timeis about 3/4 of a second.
But that's only an average. It might be less with one
driver and as long as two or three seconds or more
with another. Age, physical condition, alertness,
coordination and eyesight all play a part. So do alcohol,
drugs and frustration. But even in 3/4 of a second, a
vehicle moving at 60 mph (100 km/h) travels 66 feet
(20 m). That could be a lot of distance in an emergency,
so keeping enough space between your vehicle and
others is important.
And, of course, actual stopping distances vary greatly
with the surface of the road (whether it's pavement
or gravel); the condition of the road (wet, dry, icy); tire
tread; the condition of your brakes; the weight of
the vehicle and the amount of brake force applied.
Avoid needless heavy braking. Some people drive in
spurts Ð heavy acceleration followed by heavy braking
Ð rather than keeping pace with traffic. This is a
mistake. Your brakes may not have time to cool between
hard stops. Your brakes will wear out much faster if
you do a lot of heavy braking. If you keep pace with thetraffic and allow realistic following distances, you will
eliminate a lot of unnecessary braking. That means
better braking and longer brake life.
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 Brake System (ABS)
Your vehicle may have anti-lock brakes. ABS is an
advanced electronic braking system that will help
prevent a braking skid.
If your vehicle has anti-lock
brakes, this warning light
on the instrument panel will
come on brie¯y when
you start your vehicle.
When you start your engine, or when you 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, and you may even notice that
your brake pedal moves or pulses a little. This is normal.
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Let's say the road is wet and you're driving safely.
Suddenly, an animal jumps out in front of you. You slam
on the brakes and continue braking. 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.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. This can help you 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
®rmly and let anti-lock work for you. You may feel a
slight brake pedal pulsation or notice some noise, but
this is normal.
Braking in Emergencies
At some time, nearly every driver gets into a situation
that requires hard braking.If you have anti-lock, you can steer and brake at the
same time. However, if you don't have anti-lock,
your ®rst reaction Ð to hit the brake pedal hard and
hold it down Ð may be the wrong thing to do. Your
wheels can stop rolling. Once they do, the vehicle can't
respond to your steering. Momentum will carry it in
whatever direction it was headed when the wheels
stopped rolling. That could be off the road, into the
very thing you were trying to avoid, or into traffic.
If you don't have anti-lock, use a ªsqueezeº braking
technique. This will give you maximum braking while
maintaining steering control. You can do this by pushing
on the brake pedal with steadily increasing pressure.
In an emergency, you will probably want to squeeze the
brakes hard without locking the wheels. If you hear or
feel the wheels sliding, ease off the brake pedal.
This will help you retain steering control. If you
dohave
anti-lock, it's different. See ªAnti-Lock Brake Systemº
in this section.
In many emergencies, steering can help you more than
even the very best braking.
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Traction Control System (TCS)
(3800 V6 Engine)
Your vehicle may have a traction control system that
limits wheel spin. This is especially useful in slippery road
conditions. The system operates only if it senses that one
or both of the front wheels are spinning or beginning to
lose traction. When this happens, the system reduces
engine power and may also upshift the transaxle and
apply the front brakes to limit wheel spin.
This light will come on when your traction control
system is limiting wheel spin. See
Traction Active
Message on page 3-41.
You may feel or hear the system working, but this is
normal.
If your vehicle is in cruise control when the traction
control system begins to limit wheel spin, the cruise
control will automatically disengage. When roadconditions allow you to safely use it again, you may
re-engage the cruise control. See ªCruise Controlº
in
Turn Signal/Multifunction Lever on page 3-7.
The traction control system operates in all transaxle
shift lever positions. But the system can upshift
the transaxle only as high as the shift lever position
you've chosen, so you should use the lower gears only
when necessary. See
Automatic Transaxle Operation
on page 2-23.
When the system is on,
this warning light will come
on to let you know if
there's a problem.
See. When this warning light is on, the system will not
limit wheel spin. Adjust your driving accordingly.
To limit wheel spin, especially in slippery road conditions,
you should always leave the traction control system on.
But you can turn the system off if you ever need to. You
should turn the system off if your vehicle ever gets stuck
in sand, mud or snow and rocking the vehicle is required.
See ªRocking Your Vehicle To Get It Outº under
If You
Are Stuck: In Sand, Mud, Ice or Snow on page 4-30. United States
Canada
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Suppose you're steering through a sharp curve.
Then you suddenly apply the brakes. Both control
systems Ð steering and braking Ð have to do their
work where the tires meet the road. Unless you
have four-wheel anti-lock brakes, adding the hard
braking can demand too much of 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 Ð steering and acceleration Ð 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.
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 ªdriveº 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 ®nd
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 Ð if you can stop
in time. But sometimes you can't; there isn't room.
That's the time for evasive action Ð steering around
the problem.
Your vehicle can perform very well in emergencies like
these. First apply your brakes Ð but, unless you
have anti-lock, not enough to lock your wheels.
See
Braking on page 4-6. 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.
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·Check your mirrors, glance over your shoulder, and
start your left lane change signal before moving out
of the right lane to pass. When you are far
enough ahead of the passed vehicle to see its front
in your inside mirror, activate your right lane
change signal and move back into the right lane.
(Remember that your right outside mirror is convex.
The vehicle you just passed may seem to be
farther away from you than it really is.)
·Try not to pass more than one vehicle at a time on
two-lane roads. Reconsider before passing the
next vehicle.
·Don't overtake a slowly moving vehicle too rapidly.
Even though the brake lamps are not ¯ashing, it
may be slowing down or starting to turn.
·If you're being passed, make it easy for the
following driver to get ahead of you. Perhaps you
can ease a little to the right.
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.
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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
ªoverdrivingº 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 Ð such as enough water, ice or packed snow
on the road to make a ªmirrored surfaceº Ð and slow
down when you have any doubt.
If you have the anti-lock braking system, remember: It
helps avoid only the braking skid. If you do not have
anti-lock, then in a braking skid (where the wheels are
no longer rolling), release enough pressure on the
brakes to get the wheels rolling again. This restores
steering control. Push the brake pedal down steadily
when you have to stop suddenly. As long as the wheels
are rolling, you will have steering control.
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The heavier the rain, the harder it is to see. Even if your
windshield wiper blades are in good shape, a heavy
rain can make it harder to see road signs and
traffic signals, pavement markings, the edge of the road
and even people walking.
It's wise to keep your windshield wiping equipment in
good shape and keep your windshield washer tank ®lled
with washer ¯uid. Replace your windshield wiper
inserts when they show signs of streaking or missing
areas on the windshield, or when strips of rubber start to
separate from the inserts.Driving too fast through large water puddles or even
going through some car washes can cause problems,
too. The water may affect your brakes. Try to avoid
puddles. But if you can't, try to slow down before you
hit them.
{CAUTION:
Wet brakes can cause accidents. They won't
work as well in a quick stop and may cause
pulling to one side. You could lose control of
the vehicle.
After driving through a large puddle of water
or a car wash, apply your brake pedal lightly
until your brakes work normally.
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