GMC ENVOY DENALI 2007 Owners Manual

Your Driving, the Road, and
Your Vehicle............................................ 302
Defensive Driving...................................... 302
Drunken Driving........................................ 303
Control of a Vehicle.................................. 306
Braking...................................................... 306
Anti-Lock Brake System (ABS).................. 307
Braking in Emergencies............................. 309
Locking Rear Axle..................................... 309
StabiliTrak
®System................................... 309
Steering.................................................... 314
Off-Road Recovery.................................... 316
Passing..................................................... 316
Loss of Control.......................................... 318
Off-Road Driving........................................ 319
Driving at Night......................................... 334
Driving in Rain and on Wet Roads............ 335
City Driving............................................... 338Freeway Driving........................................ 339
Before Leaving on a Long Trip.................. 340
Highway Hypnosis..................................... 341
Hill and Mountain Roads........................... 342
Winter Driving........................................... 344
If Your Vehicle is Stuck in Sand, Mud,
Ice, or Snow.......................................... 348
Rocking Your Vehicle to Get It Out........... 348
Loading Your Vehicle................................ 349
Adding a Snow Plow or Similar
Equipment.............................................. 354
Towing........................................................ 354
Towing Your Vehicle ................................. 354
Recreational Vehicle Towing...................... 355
Electronically Controlled Air Suspension
System.................................................. 360
Towing a Trailer........................................ 362
Section 4 Driving Your Vehicle
301

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. SeeSafety Belts: They
Are for Everyone on page 20.
{CAUTION:
Defensive driving really means “Be ready
for anything.” On city streets, rural roads,
or expressways, it means “Always expect
the unexpected.” Assume that pedestrians
or other drivers are going to be careless
and make mistakes. Anticipate what they
might do and be ready. Rear-end collisions
are about the most preventable of
accidents. Yet they are common. Allow
enough following distance. Defensive
driving requires that a driver concentrate
on the driving task. Anything that distracts
from the driving task makes proper
defensive driving more difficult and can
even cause a collision, with resulting
injury. Ask a passenger to help do these
things, or pull off the road in a safe place to
do them. These simple defensive driving
techniques could save your life.
302

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
303

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.
304

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.
305

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.
Adding non-GM accessories can affect your
vehicle’s performance. SeeAccessories and
Modications on page 380.
Braking
SeeBrake System Warning Light on page 206.
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.
306

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 380.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 207.
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.
307

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.
308

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.
StabiliTrak®System
Your vehicle is equipped with StabiliTrak®,
Electronic Stability Control (ESC) which combines
antilock brake, traction and stability control systems
and helps the driver maintain directional control of
the vehicle in most driving conditions.
Traction control activates when the controller
senses wheel spin. StabiliTrak
®will selectively
apply the brakes and reduce engine torque to help
regain traction.
Stability control activates when the controller
senses a discrepancy between your intended path
and the direction the vehicle is travelling.
StabiliTrak
®selectively applies braking pressure at
any one of the vehicle’s brakes to help guide the
vehicle in the direction which you are steering.
When you rst start your vehicle and begin to drive
away, the system performs several diagnostic
checks to insure 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.
If driving conditions delay system initialization, the
STABILITRAK NOT READY message may be
displayed. If this is the case, your vehicle does not
need servicing.
309

For more information on the stability messages,
seeDIC Warnings and Messages on page 222.
When the StabiliTrak
®
system is both on and
actively controlling
the stability of the
vehicle, the StabiliTrak
®
light will blink for the
duration of the event.
You may also feel or hear the system working.
This is normal.
The StabiliTrak
®disable
button is located on the
transmission shift
handle.
The StabiliTrak
®system is automatically disabled
in 4LO mode and cannot be turned on until the
vehicle is switched to 2HI, 4HI, or 4AWD.The StabiliTrak
®system has three modes of
operation: STABILITRAK ON, TRACTION
CONTROL OFF, and STABILITRAK OFF.
STABILITRAK ON -The vehicle will default to
STABILITRAK ON every time the driver starts the
vehicle. The StabiliTrak
®light will be off and no
DIC messages will be displayed.
TRACTION CONTROL OFF - The driver can
modify the engine speed management system by
momentarily pressing the StabiliTrak
®button
on the transmission shift handle. The StabiliTrak®
light will come on and TRACTION CONTROL OFF
will be displayed. For vehicles without a DIC,
the StabiliTrak
®indicator light will come on.
Momentarily pressing the StabiliTrak®button
again will return the system to the STABILITRAK
ON mode.
STABILITRAK OFF - The driver can turn off
StabiliTrak
®by pressing the StabiliTrak®button for
more than ve seconds. The StabiliTrak®light will
come on and STABILITRAK OFF will be displayed.
For vehicles without a DIC, the StabiliTrak
®
indicator light will come on. Momentarily pressing
the StabiliTrak®button again will return the system
to the STABILITRAK ON mode. See StabiliTrak®
Off below for more information.
310