brakes GMC SIERRA 1994 Owners Manual

@ (Automatic Overdrive)
This position is for normal driving. If you need more power for
passing, and you’re:
- Going less than about 35 mph (56 km/h), push your accelerator
pedal about halfway down.
- Going about 35 mph (56 kdh) or more, push the accelerator all
the way down.
You’ll shift down to the next gear and have more power.
@ should not be used when towing a trailer, carrying a heavy load,
driving
on steep hills, or for off road driving. Select “D”(third gear)
when operating the vehicle under any
of these conditions.
D (Third Gear)
This is like @, but you never go into Overdrive. You should use “D”
when towing a trailer, carrying a heavy load, driving on steep hills, or
for off-road driving.
2 (Second Gear)
This position gives you more power but lower fuel economy. You can
use
“2” on hills. It can help control your speed as you go down steep
mountain roads, but then you would
also want to use your brakes off
and
on. If you manually select “2”, the transmission will drive in
second gear. You may use this feature for reducing torque to the rear
wheels when
you are trying to start your vehicle from a stop on
slippery road surfaces.
1 (First Gear)
This position gives you even more power (but lower fuel economy)
than
“2.” You can use it on very steep hills, or in deep snow or mud. If
the selector lever is put in “1 ,” the transmission won’t shift into first
gear
until the vehicle is going slowly enough.
b
NOTICE:
If your rear wheels can’t rotate, don’t try to drive. This might
happen if you were stuck in very deep sand or mud or were up
against
a solid object. You could damage your transmission.
Also,
if you stop when going uphill, don’t hold your vehicle there
with only the accelerator pedal. This could overheat and damage
the transmission. Use your brakes
or shift into “P” (Park) to
hold your vehicle in position on a hill.
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NOTICE:
Driving with the parking brake on can cause your rear brakes to
overheat. You may have
to replace them, and you could also
damage other parts of your vehicle.
If you are towing a trailer and are parking on any hill: See “Towing a
Trailer” in the Index. That section shows what to do first to keep the trailer
from moving.
Propshaft Brake Burnish Procedure
If you have a 3500 HD model, it is recommended that the propshaft
mounted parking brake be burnished
as part of the new vehicle break in.
The parking brake will work best after it has been burnished following these
instructions.
Make
10 (ten) stops, using the parking brake foot pedal, from 20 mph
(32 kdh) about
2 1/2 miles (4 km) apart. In between stops, drive the
vehicle at
20 mph (32 km/h).
Torque Lock
The parking brake should be set first whenever you leave the driver’s seat.
If you are parked on
a hill and the transmission is placed in “P” (Park)
before
the parking brake is set, the weight of the vehicle may put too much
force
on the parking pawl in the transmission. It may be difficult to pull the
selector lever out
of “P’ (Park). This is called “torque lock.” To prevent this,
the parking brake should be set
BEFORE moving the gear selector to “P’
(Park).
When preparing to move
a vehicle parked on a hill, the selector lever should
be moved out of
“P’ (Park) BEFORE releasing the parking brake. Even
when
on level surfaces, its a good idea to set the parking brake first before
shifting
the transmission from “P” (Park).
If torque lock does occur, you may have to have another vehicle nudge your
vehicle uphill a little to take some
of the pressure off the transmission while
you pull the selector lever out of “P” (Park).
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If you have four-wheel drive and your transfer case is in “N” (Neutral),
your vehicle will be free to roll, even
if your shift lever is in “P” (Park). So,
be sure the transfer case is in a drive gear - not in “N” (Neutral). Follow
the proper steps to be sure your vehicle won’t move. See “Shifting Into
‘P’
(Park)’’ in the Index.
If you’re pulling a trailer, see “Towing a Trailer” in the Index.
Four- Wheel Drive
If your vehicle has four-wheel drive, you can send your engine’s driving
power to all four wheels for extra traction.
To get the most satisfixtion out
of four-wheel drive, you must be familiar with it’s operation. Read
the part
that follows before using four-wheel drive.
You should use 2H for most
normal driving conditions.
Rear-wheel antilock brakes
do not work when you shift into four-wheel
drive. Your regular brakes
will still work. When you shift back into
two-wheel drive, your rear-wheel antilock brakes will take over again.
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NOTICE:
0 When using concentrated washer fluid, follow the
manufacturer’s instructions for adding water.
Don’t mix water with ready-to-use washer fluid. Water can
cause the solution to freeze and damage your washer fluid
tank and other parts of the washer system.
Also, water
doesn’t clean as well as washer fluid.
Fill your washer fluid tank only 314 full when it’s very cold.
This allows for expansion, which could damage the tank if it is
completely full.
0 Don’t use radiator antifreeze in your windshield washer. It
can damage your washer system and paint.
Cruise Control (Option)
If you have Cruise
Control,
the end of
your multifunction
lever
will look like
this.
With Cruise Control, you can maintain a speed
of about 25 mph (40 km/h)
or more without keeping your foot
on the accelerator. This can really help
on long trips. Cruise Control does not work at speeds below about 25 mph
(40 km/h).
When
you apply your brakes, the Cruise Control shuts off.
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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 you are
driving,
or when one of the gages shows there may be a problem, 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
The red brake system
warning light is
located at the bottom
right corner
of the
instrument cluster
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 parts working well.
Your vehicle also has rear-wheel anti-lock brakes.
If the warning light
comes on, there could be
a brake problem with either your regular or
rear-wheel anti-lock 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.
If the light comes on while you are driving, pull off the road and stop
carefully.
You may notice 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.)
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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.
Sometimes,
as when you’re driving on snow or ice, it‘s easy to ask more of
those control systems than the tires and road can provide. That means you
can lose control of
your vehicle.
Braking
Braking action involves perceptiorz time and renction time.
First, you have to decide to push on the brake pedal. That’spemptiorz time.
Then you have to bring up your foot and do it. That’s reaction time.
Average reaction time is about 3/4 of a second. But that’s only an average. It
might be less
with one driver and as long as two 01- 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 34 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.
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.
If you keep pace with the traffic and allow realistic following
distances, you will eliminate a lot of unnecessary braking. That means better
braking and longer brake life.
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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 an advanced electronic braking system that can help you
keep it under control.
When you start your vehicle and begin to drive away, you may hear
a
momentary motor or clicking noise. The ABS motor comes on momentarily
when
the vehicle reaches 8 mph (I 2 km/h). And you may even notice that
your brake pedal moves a little while this is going on. This
is the ABS
system testing itself.
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 the rear wheels are slowing down.
IT one of the rear
wheels is about to stop rolling, the computer will work
the brakes at the rear
wheels.
It is programmed to make the most of available tire and road
conditions.
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I- .,
As you brake, your computer keeps receiving updates on rear 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. 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.
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 front wheels stopped rolling. That could be off the
road, into the very thing you were trying to avoid, or into traffic.
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So, use a “squeeze” braking technique. This will give you maximum
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 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.
Steering lips
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.
Suppose you’re steering through
a sharp curve. Then you suddenly apply
the brakes. Both control systems
- steering and braking - have to do their
work where the tires meet the road. Adding the hard braking can demand
too much at 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 - steering and acceleration
- 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.
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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.
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 emergen.cies like these. First apply
your brakes, but not enough to lock your front wheels. 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 quicltly, and just
as quickly
straighten
the wheel once you have avoided the object.
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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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