brakes CHEVROLET ASTRO 2003 User Guide

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
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.
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 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.
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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.
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 OD
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.
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.
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3

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.
Wet brakes can cause -:cider.--. They w -.j’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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If you drive regularly in steep country, or if you’re
planning to visit there, here are some tips that can make
your trips safer and more enjoyable.
Keep your vehicle in good shape. Check all fluid
levels and also the brakes, tires, cooling system
and transmission. These parts can work hard
on mountain roads.
0 Know how to go down hills. The most important
thing to know is this: let your engine do some of
the slowing down. Shift
to a lower gear when you go
down a steep or long
hill.
0
If you don’t shift down, y--. -.-. ces coul, Jet
so hot that they wouldn’t work well. You would
then have poor braking or even none going
down a hill. You could crash. Shift down to let
your engine assist your brakes on a steep
downhill slope. Coasting downh.-.
... .rlEUTL .. _L (N) or wit
ignition
off is dangerous. Your brakes will have
to do all the work
of slowing down. They could
get
so hot that they wouldn’t work well. You
would then have poor braking or even none
going down a hill. You could crash. Always have
your engine running and your vehicle in gear
when you go downhill.
e
e
I I
e
Know how to go uphill. You may want to shift down to
a lower gear. The lower gears help cool your engine
and transmission, and you can climb the hill better.
Stay in your own lane when driving on two-lane
roads
in hills or mountains. Don’t swing wide or cut
across the center of the road. Drive at speeds that let
you stay in your own lane.
As you go over the top of a hill, be alert. There could
be something in your lane, like a stalled car or an
accident.
You may see highway signs on mountains that warn
of special problems. Examples are long grades,
passing or no-passing zones,
a falling rocks area
or winding roads. Be alert to these and take
appropriate action.
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What’s the worst time for this? “Wet ice.” Very cold
snow or ice can be slick and hard to drive on. But wet
ice can be even more trouble because it may offer
the least traction of all. You can get wet ice when it’s
about freezing
(32°F; OOC) and freezing rain begins
to fall. Try to avoid driving on wet ice until salt and sand
crews can get there. Whatever
the condition
- smooth ice, packed, blowing
or loose snow
- drive with caution.
Accelerate gently. Try not to break the fragile traction.
If you accelerate too fast, the drive wheels will spin and
polish the surface under the tires even more.
Your anti-lock brakes improve your vehicle’s stability
when you make a hard stop on a slippery road.
Even though you have an anti-lock braking system,
you’ll want to begin stopping sooner than you would
on dry pavement. See
Braking on page 4-6.
Allow greater following distance on any slippery road.
Watch for slippery spots. The road might be fine
until you hit a spot that’s covered with ice. On an
otherwise clear road, ice patches may appear in
shaded areas where the sun can’t reach:
around clumps of trees, behind buildings
or under
bridges. Sometimes the surface of a curve or an
overpass may remain icy when the surrounding
roads are clear. If you see a patch of ice ahead of
you, brake before you are on it. Try not to brake while
you’re actually on the ice, and avoid sudden steering
maneuvers.
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Payload
The Payload Capacity is shown on the CertificationiTire
label. This is the maximum load capacity that your
vehicle can carry. Be sure to include the weight of the
people inside as part of your load.
If you added any
accessories or equipment after your vehicle left
the factory, remember to subtract the weight of these
things from the payload. Your dealer can help you
with this.
Towing a Trailer
Trailering Package
There is a load rating which includes the weight of the
vehicle and the trailer it tows. This rating is called
the Gross Combination Weight Rating (GCWR).
When
you weigh your trailer, be sure to include the
weight of everything you put in it. And, remember
to figure the weight of the people inside the vehicle
as part of your load.
Add-on Equipment
When you carry removable items, you may need to put
a limit on how many people you carry inside your
vehicle. Be sure to weigh your vehicle before you buy
and install the new equipment. If
)“J don’t use the correct equipment and
drive properly, you can lose control when you pull a trailer. For example, if the trailer
is too
heavy, the brakes may not work well
- or
even at all. You and your passengers could be
seriously injured. Pull a trailer only if you have
followed all the steps in this section.
Ask your
dealer for advice and information about towing
a trailer with your vehicle.
Notice: Pulling a trailer improperly can damage
your vehicle and result in costly repairs not covered by your warranty.
To pull a trailer correctly, follow
the advice
in this part, and see your dealer for
important information about towing a trailer with
your vehicle. Additional rear axle maintenance is required for a vehicle used to tow a trailer. See
“Scheduled Maintenance Services”
in the Index.
To identify what the vehicle trailering capacity is for your
vehicle, you should read the information in “Weight of
the Trailer” that appears later in this section.
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Hitches
It’s important to have the correct hitch equipment.
Crosswinds, large trucks going by and rough roads
are a few reasons why you’ll need the right hitch.
Here are some rules to follow:
If you’ll be pulling a trailer that, when loaded, will
weigh more than
2,000 Ibs. (900 kg.), be sure to
use a properly mounted, weight-distributing
hitch and sway control of the proper size. This
equipment is very important for proper vehicle
loading and good handling when you’re driving.
Will you have to make any holes in the body of
your vehicle when you install a trailer hitch? Follow the manufacturer’s
recommendation for attaching
safety chains and do not attach them to the bumper.
Always leave just enough slack
so you can turn with
your rig. Never allow safety chains to drag on the ground.
Trailer Brakes
If your trailer weighs more than 1,000 Ibs (450 kg)
loaded, then it needs its own brakes
- and they must
be adequate. Be sure to read and follow the instructions
for the trailer brakes
so you’ll be able to install, adjust
and maintain them properly.
Your trailer brake system can tap into your vehicle’s
hydraulic brake system, except:
If you do, then be sure to seal the holes later when
you remove the hitch. If you don’t seal them,
deadly carbon monoxide
(CO) from your exhaust
can get into your vehicle. Dirt and water can, too.
Safety Chains
You should always attach chains between your vehicle
and your trailer. Cross the safety chains under the tongue
of the trailer to help prevent the tongue from contacting
the road
if it becomes separated from the hitch.
Instructions about safety chains may be provided by
the hitch manufacturer or by the trailer manufacturer. Don’t
tap into your vehicle’s brake system
if the
trailer’s brake system will use more than
0.02 cubic
inch
(0.3 cc) of fluid from your vehicle’s master
cylinder. If it does, both braking systems won’t work
well. You could even lose your brakes.
Will the trailer parts take
3,000 psi (20 650 kPa) of
pressure? If not, the trailer brake system must not
be used with your vehicle.
If everything checks out this far, then make the
brake fluid tap at the
port on the master cylinder that
sends fluid to the rear brakes. But don’t use
copper tubing for this. If you do, it will bend and
finally break
off. Use steel brake tubing.
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Driving with a Trailer
If you ~ ve a rear-most window open and
you pull a trailer with your vehicle, carbon monoxide (CO) could come into your vehicle.
You can’t see or smell
CO. It can cause
unconsciousness or death. See “Engine
Exhaust” in the Index.
To maximize your safety
when towing a trailer:
Have your exhaust system inspected for
leaks, and make necessary repairs before
starting on your trip.
Keep the rear-most windows closed.
If exhaust does come into your vehicle
through a window
in the rear or another
opening, drive with your front, main
heating or cooling system on and with the
fan on any speed. This will bring fresh,
outside air into your vehicle.
Do not use
the climate control setting for maximum air because
it only recirculates the air inside
your vehicle. See “Climate Controls” in
the Index. Towing
a trailer requires a certain amount of experience.
Before setting out for the open road, you’ll want to get
to know your rig. Acquaint yourself with the feel of
handling and braking with the added weight of the trailer.
And always keep in mind that the vehicle you are
driving is now a good deal longer and not nearly as
responsive as your vehicle is by itself.
Before you start, check the trailer hitch and platform
(and attachments), safety chains, electrical connector,
lamps, tires and mirror adjustment. If the trailer has
electric brakes, start your vehicle and trailer moving and
then apply the trailer brake controller by hand to be
sure the brakes are working. This lets you check your
electrical connection at the same time.
During your trip, check occasionally
to be sure that
the load
is secure, and that the lamps and any trailer
brakes are still working.
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