1995 GMC SIERRA Owners Manual

According to the American Medical Association, a 180-pound (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
U.S. 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.
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. Statisti\
cs 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 twelve times greater;
at a level
of 0.15 percent, the chance is twenty-five 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 cQrd 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.
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 tinze 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 reuction tinze 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; and the condition
of your brakes.
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 Brakes (ABS)
Your vehicle has an advanced electronic braking system that can help you
keep it under control. When you start your vehicle and begin to drive away,
you may hear a momentary motor or clicking noise. This is the
ABS system
testing itself.
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 the 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.
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.
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Remember: Anti-lock doesn’t change the time you need to get your foot up
to the brake pedal. 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.
To Use Anti-Lock
Don’t pump the brakes. Just hold the brake pedal down 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
Use your anti-lock braking system when you need to. 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.
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 fivorable 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. Wdit 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 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.
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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.
Off-Road Recovery
You may find sometime 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 1/4 turn until the right front tire contacts
the pavement edge. Then
turn your steering wheel to go straight down the
roadway.
1. Edge of Road
Surface
2. Slow Down
3. Left Approx. Quarter Turn
4. Recover
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Passing
The driver of a vehicle about to pass another on a two-lane highway waits
for just the right moment, accelerates, moves 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 t\
he 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:
0 “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 traffic signs, pavement markings, 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 your
side of the lane or a double solid line, even if the road seems empty of
approaching traffic.
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.
0 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.)
Do not get too close to the vehicle you want to pass while you’re
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