GMC YUKON DENALI 2005 Owners Manual

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.
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.
Remember: Anti-lock 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 anti-lock brakes.
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Using Anti-Lock
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 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.
StabiliTrak®System
Your vehicle is equipped with StabiliTrak®, 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
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. 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 STABILITY
SYS DISABLED or SERVICE STABILITY message will
be displayed. If the vehicle has gone through heavy
acceleration or braking or multiple turns during the rst
two miles of driving after starting your vehicle, the
STABILITY SYS DISABLED message may appear. If this
is the case, your vehicle does not need servicing. You will
need to turn the vehicle off and then restart it to initialize
StabiliTrak
®. If either message appears on the Driver
Information Center (DIC), and your vehicle hasn’t gone
through hard acceleration, braking or multiple turns in the
rst two miles of driving, your vehicle should be taken in
for service.
The STABILITY SYS ACTIVE message will appear on
the Driver Information Center (DIC) only when the system
is both on and activated. It means that an advanced
computer-controlled system has come on to help your
vehicle continue to go in the direction in which you’re
steering. StabiliTrak
®activates when the computer
senses that your vehicle is just starting to spin, as it might
if you hit a patch of ice or other slippery spot on the road.
When the system activates, you may hear a noise or feel
a vibration in the brake pedal. This is normal. When the
STABILITY SYS ACTIVE message is on, you should
continue to steer in the direction you want to go.
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The system is designed to help you in bad weather or
other difficult driving situations by making the most of
whatever road conditions will permit. For more
information on the stability messages, seeDriver
Information Center (DIC) on page 3-46.
StabiliTrak
®and part of
the traction control system
can be turned off or
back on by pressing the
StabiliTrak
®button located
on the instrument panel.
When the system is turned off, the traction off light will
illuminate, and the STABILITY SYS DISABLED message
will appear on the DIC to warn the driver that both the
stability system and part of the traction control system are
disabled. Your vehicle will still have brake-traction control
when StabiliTrak
®is off, but will not be able to use the
engine speed management system. See “Traction
Control Operation” next for more information.When the StabiliTrak
®system has been turned off
you may still hear system noises as a result of
the brake-traction control coming on.
To limit wheel spin and realize the full benets of the
stability enhancement system, you should normally
leave StabiliTrak
®on, but it may be necessary to turn
the system off if your vehicle is stuck in sand, mud,
ice or snow, and you want to “rock” your vehicle
to attempt to free it. It may also be necessary to turn off
the system when driving in extreme off-road conditions
where high wheel spin is required. SeeIf You Are Stuck:
In Sand, Mud, Ice or Snow on page 4-42.
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Traction Control Operation
The traction control system is part of the StabiliTrak®
system. Traction control limits wheel spin by reducing
engine power to the wheels (engine speed management)
and by applying brakes to each individual wheel
(brake-traction control) as necessary.
The traction control system is enabled automatically
when you start your vehicle, and it will activate and
display the TRACTION ACTIVE message in the Driver
Information Center (DIC) if it senses that any of the
wheels are spinning or beginning to lose traction while
driving. If you turn off StabiliTrak
®, only the brake-traction
control portion of traction control will work. The engine
speed management will be disabled. In this state, engine
power is not reduced automatically and the driven wheels
can spin more freely. This can cause the brake-traction
control to activate constantly. For more information on
the traction active message, seeDriver Information
Center (DIC) on page 3-46.Notice:If the traction off light comes on due to
heavy braking and/or because the traction control
system has been continuously active, do not
allow the wheel(s) of one axle to spin excessively.
If you do, you may be causing damage to the
transfer case. This could lead to costly repairs not
covered by your warranty.
If the brake traction-control system activates constantly
or if the brakes have heated up due to high-speed
braking, brake traction-control will be disabled and the
TRACTION SYS LIMITED message will be displayed. In
the limited mode, the traction control system will only
use engine traction-control and is limited in its ability to
provide optimal performance since the system will
not utilize brake traction-control to control slip on the
drive wheels. The system will return to normal operation
after the brakes have cooled. This can take up to
two minutes or longer depending on brake usage.
Notice:If you allow the wheel(s) of one axle to spin
excessively while the traction off, ABS and brake
warning lights and the SERVICE STABILITY
message are displayed, you could damage the
transfer case. The repairs would not be covered by
your warranty. Reduce engine power and do not
spin the wheel(s) excessively while these lights and
this message are displayed.
4-10

The traction control system may activate on dry or
rough roads or under conditions such as heavy
acceleration while turning or abrupt upshifts/downshifts
of the transmission. When this happens you may
notice a reduction in acceleration, or may hear a noise
or vibration. This is normal.
If your vehicle is in cruise control when the system
activates, the STABILITY SYS ACTIVE message will
appear on the Driver Information Center and the cruise
control will automatically disengage. When road
conditions allow you to use cruise again, you may
re-engage the cruise control. SeeCruise Control
on page 3-11.
StabiliTrak
®may also turn off automatically if it
determines that a problem exists with the system. If the
problem does not clear itself after restarting the
vehicle, you should see your dealer for service.
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 is important to take curves at a reasonable speed.
A lot of the “driver lost control” accidents mentioned on
the news happen on curves. Here is 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 is no traction, inertia
will keep the vehicle going in the same direction. If
you have ever tried to steer a vehicle on wet ice, you
will 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 are in a curve, speed is the one factor you
can control.
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Suppose you are 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 will 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.Steering in Emergencies
There are times when steering can be more effective than
braking. For example, you come over a hill and nd 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 cannot; there is not room. That is the time
for evasive action — steering around the problem.
Your vehicle can perform very well in emergencies like
these. First apply your brakes.
SeeBraking on page 4-5. 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.
4-12

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.
Off-Road Recovery
You may nd that your right wheels have dropped off the
edge of a road onto the shoulder while you are 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.
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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 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 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 is 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.
Do not get too close to the vehicle you want to
pass while you are awaiting an opportunity. For one
thing, following too closely reduces your area of
vision, especially if you are following a larger
vehicle. Also, you will not 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 do
not 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 vehicles are lined up to pass a slow vehicle,
wait your turn. But take care that someone is not
trying to pass you as you pull out to pass the slow
vehicle. Remember to glance over your shoulder and
check the blind spot.
4-14

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.
Do not overtake a slowly moving vehicle too rapidly.
Even though the brake lamps are not ashing, it may
be slowing down or starting to turn.
If you are being passed, make it easy for the
following driver to get ahead of you. Perhaps you can
ease a little to the right.
Loss of Control
Let us review what driving experts say about what
happens when the three control systems — brakes,
steering, and acceleration — do not have enough friction
where the tires meet the road to do what the driver
has asked.
In any emergency, do not give up. Keep trying to steer
and constantly seek an escape route or area of less
danger.
Skidding
In a skid, a driver can lose control of the vehicle.
Defensive drivers avoid most skids by taking reasonable
care suited to existing conditions, and by not overdriving
those conditions. But skids are always possible.
The three types of skids correspond to your vehicle’s
three control systems. In the braking skid, your wheels
are not rolling. In the steering or cornering skid, too much
speed or steering in a curve causes tires to slip and lose
cornering force. And in the acceleration skid, too much
throttle causes the driving wheels to spin.
A cornering skid is best handled by easing your foot off
the accelerator pedal.
4-15

Remember: Any traction control system helps avoid only
the acceleration skid. If your traction control system is
off, then an acceleration skid is also best handled
by easing your foot off the accelerator pedal.
If your vehicle starts to slide, ease your foot off the
accelerator pedal and quickly steer the way you want
the vehicle to go. If you start steering quickly enough,
your vehicle may straighten out. Always be ready
for a second skid if it occurs.
Of course, traction is reduced when water, snow, ice,
gravel, or other material is on the road. For safety, you
will want to slow down and adjust your driving to
these conditions. It is important to slow down on slippery
surfaces because stopping distance will be longer and
vehicle control more limited.
While driving on a surface with reduced traction, try
your best to avoid sudden steering, acceleration,
or braking, including engine braking by shifting to a
lower gear. Any sudden changes could cause the tires
to slide. You may not realize the surface is slippery
until your vehicle is skidding. Learn to recognize warning
clues — such as enough water, ice, or packed snow
on the road to make a mirrored surface — and
slow down when you have any doubt.
Remember: Any anti-lock brake system (ABS) helps
avoid only the braking skid.Operating Your All-Wheel-Drive
Vehicle Off Paved Roads
If your vehicle has 20-inch tire/wheel assemblies, you
should not drive off-road unless you are on a level, solid
surface. SeeTires on page 5-56.
Many of the same design features that help make your
vehicle responsive on paved roads during poor weather
conditions — features like all-wheel drive — help make it
much better suited for off-road use than a conventional
passenger car. Its higher ground clearance also helps
your vehicle step over some off-road obstacles. But your
vehicle does not have features like special underbody
shielding and a transfer case low gear range, things that
are usually thought necessary for extended or severe
off-road service. This guide is for operating your vehicle
off paved roads.
Also, seeBraking on page 4-5.
Off-road driving can be great fun. But it does have
some denite hazards. The greatest of these is
the terrain itself.
“Off-roading” means you have left the great North
American road system behind. Traffic lanes are not
marked. Curves are not banked. There are no
road signs. Surfaces can be slippery, rough, uphill or
downhill. In short, you have gone right back to nature.
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