2001 GMC ENVOY Owners Manual

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4-1
Section 4 Your Driving and the Road
Here you'll find information about driving on different kinds of roads and in varying weather conditions. We've also
included many other useful tips on driving.
4
-2 Your Driving, the Road and Your Vehicle
4
-3 Defensive Driving
4
-4 Drunken Driving
4
-7 Control of a Vehicle
4
-7 Braking
4
-10 Steering
4
-12 Off-Road Recovery
4
-13 Passing
4
-14 Loss of Control
4
-15 Off-Road Driving with Your
Four
-Wheel-Drive Vehicle4
-29 Driving at Night
4
-30 Driving in Rain and on Wet Roads
4
-33 City Driving
4
-34 Freeway Driving
4
-35 Before Leaving on a Long Trip
4
-36 Highway Hypnosis
4
-36 Hill and Mountain Roads
4
-38 Winter Driving
4
-41 Recreational Vehicle Towing
4
-43 Loading Your Vehicle
4
-46 Towing a Trailer
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Your Driving, the Road and
Your Vehicle
Whenever we drive, we're taking on an important
responsibility. This is true for any motor
vehicle
-- passenger car, van, truck or sport utility. Driver behavior, the driving environment, and the
vehicle's design all affect how well a vehicle performs.
But statistics show that the most important factor,
by far, is how we drive. Knowing how these three
factors work together can help you understand how
your vehicle handles and what you can do to avoid
many types of crashes, including a rollover crash.
Driver Behavior
The single most important thing is this: everyone in
the vehicle, including the driver, should buckle up.
See ªSafety Beltsº in the Index. In fact, most
serious injuries and fatalities to unbelted occupants
can be reduced or prevented by the use of safety belts.
In a rollover crash, an unbelted person is significantly
more likely to die than a person wearing a seat belt.
In addition, avoiding excessive speed, sudden or abrupt
turns and drunken or aggressive driving can help make
trips safer and avoid the possibility of a crash, especially
a rollover crash. This section provides many useful tips
to help you drive more safely.
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4-3 Driving Environment
You can also help avoid a rollover or other type of crash
by being prepared for driving in inclement weather, at
night, or during other times where visibility or traction
may be limited (such as on curves, slippery roads or
hilly terrain). Unfamiliar surroundings can also have
hidden hazards. To help you learn more about driving
in different conditions, this section contains information
about city, freeway, and off
-road driving, as well as
other hints for driving in various weather conditions.
Vehicle Design
According to the U.S. Department of Transportation,
utility vehicles have a significantly higher rollover rate
than other types of vehicles. Utility vehicles do have
a higher ground clearance and a narrower track or
shorter wheelbase than passenger cars to make them
more capable for off
-road driving. Specific design
characteristics like these give the driver a better view of
the road, but also give utility vehicles a higher center of
gravity than other types of vehicles. This means that you
shouldn't expect a utility vehicle to handle the same way
a vehicle with a lower center of gravity, like a car, would
in similar situations. But driver behavior factors are far more often the cause
of a utility vehicle rollover than are environmental or
vehicle factors. Safe driver behavior and understanding
the environment in which you'll be driving can help
avoid a rollover crash in any type of vehicle, including
utility vehicles.
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 ªSafety Beltsº in the Index.
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.
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4-4
Defensive driving requires that a driver concentrate on
the driving task. Anything that distracts from the driving
task
-- such as concentrating on a cellular telephone call,
reading, or reaching for something on the floor
-- 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.
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, about 16,000 annual motor
vehicle
-related deaths have been associated with the
use of alcohol, with more than 300,000 people injured.
Many adults
-- by some estimates, nearly half the
adult population
-- 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 solve 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 the driver 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.
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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 a liquor 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's BAC 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 when each has the
same number of drinks.
The law in many U.S. states sets the legal limit at a BAC
of 0.10 percent. In a growing number of U.S. states, and
throughout Canada, the limit is 0.08 percent. In some
other countries, it's even lower. 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.
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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
-- driver or passenger -- 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 reflexes, perceptions, attentiveness and
judgment can be affected by even a small amount
of alcohol. You can have a serious
-- or even
fatal
-- 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.
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4-7
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 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 (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.
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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.
Anti-Lock Brakes (ABS)
Your vehicle has anti-lock brakes (ABS). 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 ªAnti
-Lock Brake
System Warning Lightº in
the Index.
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