2003 Oldsmobile Bravada brakes

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 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 (1 00 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
- 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.
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.
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Anti-lock Brake System
Your vehicle has anti-lock brakes. ABS is an advanced
electronic braking system that will help prevent a
braking skid.
When you start your engine and 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. This is normal.
If there’s a problem with
~ the anti-lock brake system,
~ this warning light will
stay on. See
Anti-Lock
Brake System Warning
Light
on page 3-34.
Along with ABS, your vehicle has a Dynamic Rear
Proportioning (DRP) system. If there’s a DRP problem,
both the brake and ABS warning lights will come on
accompanied by a IO-second chime. The lights
and chime will come on each time the ignition
is turned
on until the problem is repaired. See your dealer for
service. 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.
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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. 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
firmly and let anti-lock work for you. You may feel
the brakes vibrate, or you may notice some noise, but
this is normal.
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.
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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.
Suppose you’re steering through a sharp curve. Then you
suddenly accelerate. Both control systems
- steering
and acceleration
- have to do their work where the tires
meet the road. Adding the sudden acceleration can
demand
too much of those places. You can lose control.
See
Traction Assist System (TAS) on page 4-9.
What should you do if this ever happens? Ease up on
the 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 “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 emergencies like
these. First apply your brakes.
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 flashing, 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.
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
“overdriving” 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 is best handled by easing your foot off
the accelerator pedal.
If you have the Traction Assist System, remember: It
helps avoid only the acceleration skid.
If you do not have
this system, or
if the system is off, then an acceleration
skid
is also 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.
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Q: Suppose, after stalling, I try to back down the
hill and decide
I just can’t do it. What
should
I do?
A: Set the parking brake, put your transmission in
PARK (P) and turn
off the engine. Leave the
vehicle and go get some help. Exit on the uphill
side and stay clear of the path the vehicle would
take
if it rolled downhill.
Driving Downhill
When off-roading takes you downhill, you’ll want to
consider a number of things:
How steep is the downhill? Will I be able to maintain
vehicle control?
What’s the surface like? Smooth? Rough? Slippery?
Are there hidden surface obstacles? Ruts? Logs?
Hard-packed dirt? Gravel?
Boulders?
What’s at the bottom of the hill? Is there a there a
hidden creek bank or even a river bottom with
large rocks?
If you decide you can go down a hill safely, then
try to
keep your vehicle headed straight down, and use a
low gear. This way, engine drag can help your brakes
and they won’t have
to do all the work. Descend slowly,
keeping your vehicle under control at all times.
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Heavy braki.., when going down a hill can
cause your brakes to overheat and fade. This
could cause
loss of control and a serious
accident. Apply the brakes lightly when
descending a hill and use a low gear to keep
vehicle speed under control.
Q: Are there some things I should not do when
driving down
a hill?
A: Yes! These are important because if you ignore
them you could
lose control and have a serious
accident.
When driving downhill, avoid turns that take you
across the incline
of the hill. A hill that’s not too
steep to drive down may be too steep to drive
across. You could roll over
if you don’t drive straight
down.
Never go downhill with the transmission in
NEUTRAL (N). This is called “free wheeling”. Your
brakes will have to do all the work and could
overheat and fade.

Q: Am I likely to stall when going downhill?
A: It’s much more likely to happen going uphill. But if it
happens going downhill, here’s what to do.
Apply the parking brake.
engine.
and drive straight down.
Stop your vehicle by applying the regular brakes.
Shift to PARK (P) and, while still braking, restart the
Shift back to a low gear, release the parking brake,
If the engine won’t start, get out and get help.
Driving Across an Incline
Sooner or later, an off-road trail will probably go across
the incline of a hill. If this happens, you have to
decide whether to try to drive across the incline. Here
are some things to consider:
A hill that can be driven straight up or down may be
too steep to drive across. When you go straight up
or down a hill, the length of the wheel base (the distance from
the front wheels to the rear wheels)
reduces the likelihood the vehicle will tumble
end over end. But when you drive across an incline,
the much more narrow track width (the distance
between the left and right wheels) may not prevent
the vehicle from tilting and rolling over.
Also,
driving across an incline puts more weight on the
downhill wheels. This could cause
a downhill
slide or a rollover.
Surface conditions can be a problem when you
drive across a hill. Loose gravel, muddy spots,
or even wet grass can cause your tires to slip
sideways, downhill.
If the vehicle slips sideways, it
can hit something that will trip it (a rock, a rut,
etc.) and roll over.
Hidden obstacles can make the steepness of the
incline even worse.
If you drive across a rock with the
uphill wheels, or it the downhill wheels drop into a rut
or depression, your vehicle can tilt even more.
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Driving in Water
Heavy rain can mean flash flooding, and flood waters
demand extreme caution.
Find out how deep the water is before you drive through
it.
If it’s deep enough to cover your wheel hubs, axles
or exhaust pipe, don’t try
it - you probably won’t
get through. Also, water that deep can damage your
axle and other vehicle parts.
If the water isn’t too deep, drive slowly through it. At
faster speeds, water splashes on your ignition system
and your vehicle can stall. Stalling can also occur
if you
get your tailpipe under water. And, as long as your
tailpipe
is under water, you’ll never be able to start your
engine. When you go through water, remember that
when your brakes get wet, it may take you longer
to stop.
Driving through rushing water can be
dangerous. Deep water can sweep your vehicle
downstream and you and your passengers
CAUTION: (Continued)
1
coula arowr r it’s y snallo‘ Mater, can
still wash away the ground from under your
tires, and you could lose traction and roll the
vehicle over. Don’t drive through rushing
water.
See Driving in Rain and on Wet Roads on page 4-28 for
more information on driving through water.
After Off-Road Driving
Remove any brush or debris that has collected on the
underbody, chassis or under the hood. These
accumulations can be a fire hazard.
After operation in mud or sand, have the brake linings
cleaned and checked. Theses substances can cause
glazing and uneven braking. Check the body structure,
steering, suspension, wheels, tires and exhaust
system for damage.
Also, check the fuel lines and
cooling system for any leakage.
Your vehicle will require more frequent service due
to
off-road use. Refer to the Maintenance Schedule
for additional information.
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