2003 CHEVROLET AVALANCHE Owners Manual

Your Driving, the Road, and
Your Vehicle
Defensive Driving
The best advice anyone can give about driving is: Drive
defensively.
Please start with a very important safety device in your
vehicle: Buckle up. See
Safety Belts: They Are for
Everyone on page 1-10.
Defensive driving really means ªbe ready for anything.º
On city streets, rural roads or freeways, it means
ªalways expect the unexpected.º
Assume that pedestrians or other drivers are going to
be careless and make mistakes. Anticipate what
they might do. Be ready for their mistakes.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.
Defensive driving requires that a driver concentrate on
the driving task. Anything that distracts from the
driving task Ð such as concentrating on a cellular
telephone call, reading, or reaching for something on
the ¯oor Ð makes proper defensive driving more difficult
and can even cause a collision, with resulting injury.
Ask a passenger to help do things like this, or pull off the
road in a safe place to do them yourself. These simple
defensive driving techniques could save your life.
4-2

Drunken Driving
Death and injury associated with drinking and driving is
a national tragedy. It's the number one contributor to
the highway death toll, claiming thousands of victims
every year.
Alcohol affects four things that anyone needs to drive a
vehicle:
·Judgment
·Muscular Coordination
·Vision
·Attentiveness.
Police records show that almost half of all motor
vehicle-related deaths involve alcohol. In most cases,
these deaths are the result of someone who was
drinking and driving. In recent years, more than
16,000 annual motor vehicle-related deaths have been
associated with the use of alcohol, with more than
300,000 people injured.Many adults Ð by some estimates, nearly half the adult
population Ð choose never to drink alcohol, so they
never drive after drinking. For persons under 21,
it's against the law in every U.S. state to drink alcohol.
There are good medical, psychological and
developmental reasons for these laws.
The obvious way to eliminate the leading highway
safety problem is for people never to drink alcohol and
then drive. But what if people do? How much is ªtoo
muchº if someone plans to drive? It's a lot less
than many might think. Although it depends on each
person and situation, here is some general information
on the problem.
The Blood Alcohol Concentration (BAC) of someone
who is drinking depends upon four things:
·The amount of alcohol consumed
·The drinker's body weight
·The amount of food that is consumed before and
during drinking
·The length of time it has taken the drinker to
consume the alcohol.
4-3

According to the American Medical Association, a 180 lb
(82 kg) person who drinks three 12 ounce (355 ml)
bottles of beer in an hour will end up with a BAC
of about 0.06 percent. The person would reach the
same BAC by drinking three 4 ounce (120 ml) glasses
of wine or three mixed drinks if each had 1-1/2 ounces
(45 ml) of liquors like whiskey, gin or vodka.
It's the amount of alcohol that counts. For example, if
the same person drank three double martinis (3 ounces
or 90 ml of liquor each) within an hour, the person'sBAC would be close to 0.12 percent. A person who
consumes food just before or during drinking will have a
somewhat lower BAC level.
There is a gender difference, too. Women generally
have a lower relative percentage of body water
than men. Since alcohol is carried in body water, this
means that a woman generally will reach a higher BAC
level than a man of her same body weight will when
each has the same number of drinks.
The law in an increasing number of U.S. states, and
throughout Canada, sets the legal limit at 0.08 percent.
In some other countries, the limit is even lower. For
example, it is 0.05 percent in both France and Germany.
The BAC limit for all commercial drivers in the United
States is 0.04 percent.
The BAC will be over 0.10 percent after three to six
drinks (in one hour). Of course, as we've seen, it
depends on how much alcohol is in the drinks, and how
quickly the person drinks them.
4-4

But the ability to drive is affected well below a BAC of
0.10 percent. Research shows that the driving skills
of many people are impaired at a BAC approaching
0.05 percent, and that the effects are worse at night. All
drivers are impaired at BAC levels above 0.05 percent.
Statistics show that the chance of being in a collision
increases sharply for drivers who have a BAC of
0.05 percent or above. A driver with a BAC level of
0.06 percent has doubled his or her chance of having a
collision. At a BAC level of 0.10 percent, the chance
of this driver having a collision is 12 times greater; at a
level of 0.15 percent, the chance is 25 times greater!
The body takes about an hour to rid itself of the alcohol
in one drink. No amount of coffee or number of cold
showers will speed that up. ªI'll be carefulº isn't the right
answer. What if there's an emergency, a need to
take sudden action, as when a child darts into the
street? A person with even a moderate BAC might not
be able to react quickly enough to avoid the collision.There's something else about drinking and driving that
many people don't know. Medical research shows
that alcohol in a person's system can make crash
injuries worse, especially injuries to the brain, spinal
cord or heart. This means that when anyone who
has been drinking Ð driver or passenger Ð is in a
crash, that person's chance of being killed or
permanently disabled is higher than if the person had
not been drinking.
{CAUTION:
Drinking and then driving is very dangerous.
Your re¯exes, perceptions, attentiveness and
judgment can be affected by even a small
amount of alcohol. You can have a serious Ð
or even fatal Ð collision if you drive after
drinking. Please don't drink and drive or ride
with a driver who has been drinking. Ride
home in a cab; or if you're with a group,
designate a driver who will not drink.
4-5

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. Also see
Traction Assist System
(TAS) on page 4-10.
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.
4-6

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 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.
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 3-38
.
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 10-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.
4-7

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.
4-8

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
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.
Supplemental Brake Assist System
If your vehicle has vacuum assist power brakes, it is also
equipped with a supplemental brake assist system
that supplies additional vacuum to the vacuum brake
booster if engine vacuum is reduced. Under certain
conditions, the supplemental brake assist system may
run brie¯y after starting your vehicle or when you
apply and release the brake pedal and it may continue
to run even after you have removed your foot from
the brake pedal. When the supplemental brake assistsystem is operating, you may hear a motor running or
feel a slight vibration in the steering wheel or brake
pedal. This indicates that the supplemental brake assist
system is working to supply additional vacuum for
your vacuum assist power brakes. This is a normal
operation of your brake system and does not require that
the brake system be serviced.
Each time you start your vehicle and accelerate to 10
mph, the supplemental brake assist system will perform
a self-diagnostic check of the system and you may
hear or feel the supplemental brake assist motor run
brie¯y. While you are driving your vehicle, the
supplemental brake assist system monitors itself to
ensure that it is operating properly. If there is a problem
with the supplemental brake assist system, the
SERVICE BRAKE BOOSTER message will be displayed
on the Driver Information Center. See
DIC Warnings
and Messages on page 3-57.
If your supplemental brake assist system runs every
time you apply and release the brake pedal or you notice
that the brake pedal has suddenly become much
harder to push and the vehicle takes longer to stop, you
should have your vehicle serviced as soon as possible.
4-9