2007 CHEVROLET SILVERADO Owners Manual

Drunken Driving
Death and injury associated with drinking and
driving is a national tragedy. It is 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 — by some estimates, nearly half the
adult population — choose never to drink alcohol,
so they never drive after drinking. For persons
under 21, it is 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 “too much” if someone plans
to drive? It is 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 liquors like
whiskey, gin, or vodka.It is 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 will
when each has the same number of drinks.
The law in most 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
have 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. “I will be careful”
is not the right answer. What if there is 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 is something else about drinking and driving
that many people do not 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 reexes, 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 do not drink and drive or ride with a
driver who has been drinking. Ride home in
a cab; or if you are with a group, designate
a driver who will not drink.
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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 are driving on snow
or ice, it is easy to ask more of those control
systems than the tires and road can provide.
That means you can lose control of your vehicle.
SeeStabiliTrak
®System on page 384.
Adding non-GM accessories can affect your
vehicle’s performance. SeeAccessories and
Modications on page 488.
Braking
SeeBrake System Warning Light on page 258.
Braking action involves perception time and
reaction time.
First, you have to decide to push on the brake
pedal. That is perception time. Then you have to
bring up your foot and do it. That is reaction time.
Average reaction time is about three-fourths of a
second. But that is 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 three-fourths 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 is
pavement or gravel; the condition of the road,
whether it is wet, dry, or icy; tire tread; the
condition of the 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. The brakes may not have
time to cool between hard stops. The 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 vehicle’s engine ever stops while you
are driving, brake normally but do not pump the
brakes. If you do, the pedal may get harder
to push down. If the 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.
Adding non-GM accessories can affect your
vehicle’s performance. SeeAccessories and
Modications on page 488.Anti-Lock Brake System (ABS)
Your vehicle has the Anti-Lock Brake System
(ABS), an advanced electronic braking system that
will help prevent a braking skid.
When you start your engine and begin to drive
away, ABS will check itself. You may hear a
momentary motor or clicking noise while this test
is going on. This is normal.
If there is a problem
with ABS, this warning
light will stay on.
SeeAnti-Lock Brake
System Warning
Light on page 259.
Along with ABS, your vehicle has a Dynamic Rear
Proportioning (DRP) system. If there is 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.
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Let us say the road is wet and you are driving
safely. Suddenly, an animal jumps out in front of
you. You slam on the brakes and continue braking.
Here is 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.ABS 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: ABS does not 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 will
not 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 ABS.
Using ABS
Do not 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 ABS, you can steer and brake at the same
time. In many emergencies, steering can help you
more than even the very best braking.
Locking Rear Axle
If your vehicle has this feature, your locking rear
axle can give you additional traction on snow,
mud, ice, sand or gravel. It works like a standard
axle most of the time, but when one of the
rear wheels has no traction and the other does,
this feature will allow the wheel with traction
to move the vehicle.
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StabiliTrak®System
Your vehicle may be equipped with the StabiliTrak®
system which combines antilock brake, traction and
stability control systems and helps the driver
maintain directional control of the vehicle in most
driving conditions.
When you rst start your vehicle and begin to drive
away, the system performs several diagnostic
checks to ensure there are no problems. You may
hear or feel the system working. This is normal and
does not mean there is a problem with your vehicle.
The system should initialize before the vehicle
reaches 20 mph (32 km/h). In some cases, it may
take approximately two miles of driving before the
system initializes.
If the system fails to turn on or activate, the
StabiliTrak
®light along with one of the following
messages will be displayed on the Driver
Information Center (DIC): TRACTION CONTROL
OFF, SERVICE TRACTION CONTROL,
STABILITRAK OFF, SERVICE STABILITRAK.If these DIC messages appear, make sure the
StabiliTrak
®system has not been turned off using
the StabiliTrak®on/off button. Then turn the
steering wheel clockwise from the nine o’clock
position to the three o’clock position. If this clears
the message(s), your vehicle does not need
servicing. If this does not clear the message(s),
then turn the vehicle off, wait 15 seconds, and then
turn it back on again to reset the system. If any
of these messages still appear on the Driver
Information Center (DIC), your vehicle should be
taken in for service. For more information on
the DIC messages, seeDriver Information
Center (DIC) on page 269.
The StabiliTrak
®light
will ash on the
instrument panel cluster
when the system is
both on and activated.
You may also feel or hear the system working;
this is normal.
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