brake GMC SIERRA 1993 Owner's Manual

you know they’re working. If you are familiar. with this section, you should not
be alarmed when this happens.
Gages can indicate when there may be or is _a problem with one of your
vehicle’s functions. Often gages and warning lights work together
to let you
know when there’s a problem with your vehicle.
When one of the warning lights comes on and stays on when yo\
u are driving, or when one of the gages shows there may be a probl\
em, check the
section that tells you what to do about it. Please follow the\
manual’s advice.
Waiting to do repairs can be costly-and even dangerous.
So please get to
know your warning lights and gages. They’re a big help.
Brake System. Warning Light
BRAKE
. , K2325
Your vehicle’s hydraulic brake system is divided into two parts. If ,one‘ part
isn’t working, the other part can still work and stop you. \
For good braking,
though, you need both- systems working well.
Your vehicle also has rear-wheel antilock brakes.
If the warning light goes on,
there could be a brake problem with either your regular or rear wheel antilock
brakes, or both. Have your brake system inspected right away.
This light should come on as you start the vehicle.
If it doesn’t come on
then, have
it fixed so it will be ready to warn you if there’s a problem.
This light
will also come on when you set your parking brake, and will stay
on
if your parking brake doesn’t release fully. If it stays on after your parking
brake is fully released,
it means you may ‘have a brake problem. If the light
comes on while driving, pull
off the road and stop carefully. You may notice
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Features & Controls
that the pedal is harder to push. Or, the pedal may go closer to the floor.\
It
may take longer to stop. If the light is still on, have the vehicle towed for
service. (See “Towing Your Vehicle” in the Index.)
CAUTION
* Your brake system may not be working properly if the brake warning
light is on. Driving with the brake warning light on can lead\
to an
accident.
If the light is still on after you’ve pulled off the road and
stopped carefully, have
+hq vehicle towed for service.
“WATER IN FUEL” Light
WATER
IN
FUEL I
-l PB010
This light will come on to warn you if there is too much water in the diesel
fuel system. For more information on how this light works, see\
“Diesel Fuel
Requirements and Fuel System” in the Index.
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Pavement Markings
NO PASSING ZONE
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Pavement markings add to traffic signs and signals. They give information to
drivers without taking attention from the roadway. A solid yellow line on your
side
of the road or lane means “don’t cross.”
Your Own Signals
Drivers signal to others, too. It’s not only more polite, it’s safer to let other
drivers know what you are doing. And in some places the law requires driver
signals.
Turn and lane change signals: Always signal when you plan to turn or
change lanes.
If necessary, you can use hand signals out the window: Left arm \
straight out
for a left turn, down for
slow or about-to-stop, and up for a right turn.
Slowing down: If time allows, tap the brake pedal once or twice in advance
of slowing or stopping. This warns the driver behind you.
Disabled: Your four-way flashers signal that your vehicle is disabled or is a
hazard. See “Hazard Warning Flasher” in the Index.
Traffic Officer
The traffic police officer is also a source of important informaaon. The officer’s
signals govern, no matter what the traffic lights or other sig\
ns say.
The next part discusses some of the road conditions you may e\
ncounter.
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Your Driving and the Road
Defensive Driving
The best advice anyone can give about driving is: Drive defens\
ively. Please start with a very important safety device in your vehicle: Buckle up,
(See “Safety Belts” in the Index.)
Defensive driving really means “be ready for anything.” On\
city streets, rural
roads, or freeways, it means “always expect the unexpected.’’
Assume that pedestrians or other drivers are going to be carel\
ess and make mistakes. Anticipate what they might
do. Be ready for their mistakes.
Expect children to dash out from behind parked cars, often fol\
lowed by other
children. Expect occupants in parked cars to open doors into traffic. Watch for
movement
in parked cars-someone may be about to open a door,
Expect other drivers to run stop signs when you are on a through street, Be
ready to brake
if necessary as you go through intersections. You may not
have to use the brake, but
if you do, you will be ready,
If you’re driving through a shopping center parking lot where there are
well-marked lanes, directional arrows, and designated parking are\
as, expect
some drivers to ignore all these markings and dash straight to\
ward one part
of the lot.
Pedestrians can be careless. Watch for them. In general, you must give way
to pedestrians even
if you know you have the right of way.
Rear-end collisions are about the most preventable of accidents. Yet they are
common. Allow enough following distance.
It’s the best defensive driving
maneuver, in both city and rural driving. You never know when the vehicle in
front of you is going to brake or turn suddenly.
Here’s a final bit of information about defensive driving. The most dangerous
time for driving in the
US. is very early on Sunday morning. In fact, GM
Research studies show that the most and the least dangerous times for
driving, every week, fall on the same day. That day is Sunday. The most
dangerous time is Sunday
3 a.m. to 4 a.m. The safest time is Sunday from
10 a.m. to 11 a.m. Driving the same distance on a Sunday at 3 a.m. isn’t
just a little more dangerous than it
is at 10 a.m. It’s about 134 times more
dangerous.
That leads to the next part.
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Your Driving and the Road
Control of a Vehicle
You have three systems that make your vehicle go where you want it to go.
They are the brakes, the steering and the accelerator.
All three systems have
to
do their work at the places where the tires meet the road.
AM409002
Sometimes, as when you’re driving on snow or ice, it’s e\
asy to ask more of
those control systems than the tires and road can provide. Tha\
t means you can
lose control of your vehicle.
Braking
Braking action involves perception time and reaction time.
First, you have to decide to push on the brake pedal. That’s perception
time.
Then you have to bring up your foot and do it. That’s reaction time.
Average reaction time is about 314 of a second. But that’s only an average.
It might be less with one driver and as long as two or thre\
e seconds or
more with another. Age, physical condition, alertness, coordinati\
on, 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; and the condition of your brakes,
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Most drivers treat their brakes with care. Some, however, overw\
ork the
braking system with poor driving habits.
Avoid needless heavy braking. Some people drive in spurts-heavy
acceleration followed by heavy braking-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.
Don’t “ride” the brakes by letting your left foot rest\
lightly on the brake
pedal while driving.
I
I
AM410001
CAUTION I
1 “Riding” your brakes can cause them to overheat to the point that
- they won’t work well. You might not be able to stop your vehicle in
time to avoid an accident. If you “ride” your brakes, they will get
so
hot they will require a lot of pedal force to slow you down. Avoid
“riding” the brakes.
NOTICE
“Riding” the brakes wears them out much faster. You would need costly
brake replacement much sooner than normal. and it also reduces fuel
economv.
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If you keep pace with the traffic and alllow realieti~ following dbtances, ‘you
will eliminate a lot .of unnecessary braking.. That means - better brakin’g . and
longer brake life;
,* If your engine ever stops while- you’re driving, brake normally but don’t
pump your brakes. If you do, tht$ pedal may get harder to. .push down. If
your- engine stops, you will still have some power $rake, 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 vehicl’e has an ‘advanced electronic braking system that can help keep it
under Control.
When you turn your key on you m.ay .hear a momentary clicking ngise. , ,.
Here’s I how anti-lock .works. Let’s say the road is wet. You’re d.rivilng. sifely.
Suddenly an animal jumps out In frqnt of you.
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AM41 501 6
As you brake, your computer keeps receiving updates on rear wheel spee\
d
and controls braking pressure accordingly.
CAUTION I
A
Anti-lock doesn’t change the time you need to get your foot up to I
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.
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Your Driving and fhe Road
Brake System Warning Light
K2325
This light appears on your instrument cluster to warn you if your regular
braking’ system needs service. See “Brake System Warning L\
ight” in the
Index.
Disc Brake Wear Indicators
If you have a C 3500 HD Model, it has four-wheel disc brakes. Disc brake
pads have built-in wear indicators that make a high-pitched war\
ning sound
when the brake pads are worn and new pads are needed. The so\
und m’ay
come and go or be heard all the time your vehicle is moving (except \
when
you are pushing on the brake pedal firmly).
1 CAUTION
The brake wear warning sound means that sooner or later your
hear the brake wear warning sound, have your vehicle serviced. \
5 brakes won’t work well. That could lead to an accident. When you I ~
I 1
i
~ i
brakes are first applied or lightly applied. This does not mea\
n something is
wrong with your brakes.
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Rear Drum Brakes
If you have rear drum brakes, they 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
tires are removed for rotation or changing. When you have the \
front brakes 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 Adjusiment
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
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 wheels stopped rolling. That could be off the \
road, into the
very thing you were trying to avoid, or into traffic.
So, use a “squeeze” braking technique. This will give you max\
imum 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 Sieerhg
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.
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