GMC SIERRA 1998 Owners Manual
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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, over
17,000 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
2 1, 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 this highway safety problem
is for people never to drink alcohol and then drive. But
what
if people do? How much is “too much” 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
The length of time it has taken the drinker to
during drinking
consume the alcohol.
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 - 112 ounces
(45 ml) of a liquor like whiskey, gin or vodka.
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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. I0 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.
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!
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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.
“I’ll be careful” 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.
A 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.
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.
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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.
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 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.
(@!
ANTI -
If there’s a problem with
the anti-lock brake system,
this warning light will stay
on. See “Anti-Lock Brake
System Warning Light”
in
I LOCK I the Index. 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 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 brlzke pressure faster
than any driver could. The computer is programmed
to
make the most of available tire and road conditions.
You can 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. On vehicles
with four-wheel drive, your
anti-lock brakes work at all times
-- whether you are in
two-wheel drive or four-wheel drive.
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.
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.
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Speed Sensitive Steering
This system varies the amount of steering effort
proportionate
to your vehicle speed. Steering is easier at
lower speeds for maneuvering and parking ease.
As your
vehicle speed increases,
the steering effort also
increases.
At highway speeds, the amount of steering
effort is increased for vehicle control and stability.
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.
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.
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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 in
Emergencies’’ earlier in this section.)
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 quickly, and
just as quickly straighten the wheel once you have
avoided
the object.
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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Off-Road Recovery Passing
You may find that your right wheels have dropped off the
edge of
a road onto the shoulder while you‘re driving.
If the level of the shoulder is only slightly below the
pavement, recovery should be fairly easy. Ease off the
accelerator and then,
if there is nothing in the way. steer
so that your vehicle straddles the edge of the pavement.
You can turn the steering wheel up to one-quarter turn
until the right front tire contacts the pavement edge.
Then
turn your steering wheel to go straight down
the roadway. The driver
of a vehicle about to pass another on a
two-lane highway waits
for just the right moment,
accelerates, lnoves around the vehicle ahead, then goes
back into the right
lane again. A simple maneuver‘?
Not necessarily! Passing another vehicle on a two-lane
highway is
a potentially dangerous move, since the
passing vehicle occupies the same lane as oncoming
traffic for several seconds.
A miscalculation, an error in
judgment, or a brief surrender to frustration or anger can
suddenly
put the passing driver face to face with the
worst of all traffic accidents -- the head-on collision.
So here are some tips for passing:
“Drive ahead.” Look down the road, to the sides and to
crossroads for situations that might affect your passing
patterns.
If you have any doubt whatsoever about
making a successful pass, wait for a better time.
Watch for traff‘ic signs, pavernent rnarkings and lines.
If you can see a sign up ahead that might indicate a
turn or an intersection, delay your pass. A broken
center line usually indicates it‘s all right to pass
(providing the road ahead is clear). Never cross
a solid
line on
YOLII- side of the lane or a double solid line,
even if the road seems empty of approaching traffic.
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Do not get too close to the vehicle you want to pass
while you’re awaiting
an opportunity. For one thing,
following too closely reduces your area
of vision,
especially if you’re following a larger vehicle.
Also, you
won’t have adequate space if the vehicle ahead suddenly
slows or stops. Keep back a reasonable distance.
When it looks like a chance to pass is coming up,
start
to accelerate but stay in the right lane and don’t
get too close. Time your move
so you will be
increasing speed as the time comes
to move into the
other lane. If
the way is clear to pass, you will have a
“running start” that more than makes up for the
distance you would lose by dropping back. And if
something happens to cause you to cancel your pass,
you need only slow down and drop back again and
wait for another opportunity.
If other cars are lined up to pass a slow vehicle, wait
your turn. But take care that someone
isn’t trying to
pass you as you pull
out to pass the slow vehicle.
Remember
to glance over your shoulder and check
the blind spot.
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 if
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.
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