2003 GMC YUKON Owner's Manual

Your Driving, the Road, and Your Vehicle..........4-2
Defensive Driving...........................................4-2
Drunken Driving.............................................4-2
Control of a Vehicle........................................4-6
Braking.........................................................4-6
Traction Assist System (TAS).........................4-10
Locking Rear Axle........................................4-12
Stabilitrak
®System.......................................4-12
Steering......................................................4-14
QUADRASTEER™........................................4-16
Off-Road Recovery.......................................4-19
Passing.......................................................4-20
Loss of Control.............................................4-21
Off-Road Driving with Your Four-Wheel-Drive
Vehicle
....................................................4-22
Driving at Night
............................................4-37Driving in Rain and on Wet Roads..................4-39
City Driving..................................................4-42
Freeway Driving...........................................4-43
Before Leaving on a Long Trip.......................4-44
Highway Hypnosis........................................4-44
Hill and Mountain Roads................................4-45
Winter Driving..............................................4-47
If You Are Stuck: In Sand, Mud, Ice or Snow . . .4-52
Towing..........................................................4-54
Towing Your Vehicle.....................................4-54
Recreational Vehicle Towing...........................4-55
Loading Your Vehicle....................................4-58
Level Control...............................................4-59
Autoride™...................................................4-60
Trailer Recommendations...............................4-60
Towing a Trailer...........................................4-61
Section 4 Driving Your Vehicle
4-1
2003 - Yukon/Yukon XL

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 1-22.
Defensive driving really means “be ready for anything.”
On city streets, rural roads or freeways, 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. 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.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 oor — 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.
4-2
2003 - Yukon/Yukon XL

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’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 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’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.
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.
4-3
2003 - Yukon/Yukon XL

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, thismeans 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 an increasing number of 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’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!
4-4
2003 - Yukon/Yukon XL

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.
{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.
4-5
2003 - Yukon/Yukon XL

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. Also seeTraction Assist
System (TAS) on page 4-10.
Braking
Braking action involvesperception timeand
reaction time.
First, you have to decide to push on the brake pedal.
That’sperception time.Then you have to bring up your
foot and do it. That’sreaction time.
Averagereaction timeis 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
4-6
2003 - Yukon/Yukon XL

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 Brake System
Your vehicle has anti-lock brakes. 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. SeeAnti-Lock
Brake System Warning
Light on page 3-44.
Along with ABS, your vehicle has a Dynamic Rear
Proportioning (DRP) system. If there’s 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.
4-7
2003 - Yukon/Yukon XL

Let’s say the road is wet and you’re driving safely.
Suddenly, an animal jumps out in front of you. You slam
on the brakes and continue braking. 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.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. 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.
4-8
2003 - Yukon/Yukon XL