2008 GMC ACADIA ABS

Antilock Brake System
Warning Light
For vehicles with
the Antilock Brake
System (ABS), this
light will come on
briey when you
start the engine.
That is normal. If the light does not come on then, have it
xed so it will be ready to warn you if there is a problem.
If the ABS light stays on, turn the ignition off, if the light
comes on when you are driving, stop as soon as it is
safely possible and turn the ignition off. Then start the
engine again to reset the system. If the ABS light still
stays on, or comes on again while you are driving,
your vehicle needs service. If the regular brake system
warning light is not on, you still have brakes, but you
do not have antilock brakes. If the regular brake system
warning light is also on, you do not have antilock
brakes and there is a problem with your regular brakes.
SeeBrake System Warning Light on page 3-47
For vehicles with a Driver Information Center (DIC),
seeDIC Warnings and Messages on page 3-66for
all brake related DIC messages.
StabiliTrak®Indicator Light
This warning light should
come on briey when
the engine is started.
If the warning light does not come on then, have it
xed so it will be ready to warn you if there is a problem.
If it stays on, or comes on when you are driving,
there may be a problem with your StabiliTrak
®system
and your vehicle may need service. When this warning
light is on, the system is off and will not limit wheel
spin. Adjust your driving accordingly.
This light will also ash when the StabiliTrak
®system
is active.
If the StabiliTrak
®system warning light comes on
and stays on for an extended period of time when
the system is turned on, your vehicle needs service.
SeeStabiliTrak
®System on page 4-6for more
information.
3-48

DIC Warnings and Messages
Messages are displayed on the DIC to notify the driver
that the status of the vehicle has changed and that
some action may be needed by the driver to correct
the condition. Multiple messages may appear one after
another.
Some messages may not require immediate action,
but you can press any of the DIC buttons on the
instrument panel or the trip odometer reset stem on
the instrument panel cluster to acknowledge that
you received the messages and to clear them from
the display.
Some messages cannot be cleared from the DIC
display because they are more urgent. These messages
require action before they can be cleared. You should
take any messages that appear on the display seriously
and remember that clearing the messages will only
make the messages disappear, not correct the problem.
The following are the possible messages that can be
displayed and some information about them.
ALL WHEEL DRIVE OFF
If your vehicle has the All-Wheel Drive (AWD) system,
this message displays when there is a compact
spare tire on the vehicle, when the Antilock Brake
System (ABS) warning light comes on, or when the
rear differential uid is overheating. This message
turns off when the differential uid cools.
The AWD system is disabled until the compact spare
tire is replaced by a full-size tire. If the warning message
is still on after putting on the full-size tire, you need to
reset the warning message. To reset the warning
message, turn the ignition off and then back on again
after 30 seconds. If the message stays on, see your
dealer/retailer right away. SeeAll-Wheel Drive (AWD)
System on page 4-9for more information.
AUTOMATIC LIGHT CONTROL OFF
This message displays when the automatic
headlamps are turned off. This message clears
itself after 10 seconds.
AUTOMATIC LIGHT CONTROL ON
This message displays when the automatic
headlamps are turned on. This message clears
itself after 10 seconds.
3-66

Your Driving, the Road, and Your Vehicle..........4-2
Defensive Driving...........................................4-2
Drunk Driving.................................................4-2
Control of a Vehicle........................................4-3
Braking.........................................................4-4
Antilock Brake System (ABS)...........................4-5
Braking in Emergencies...................................4-6
StabiliTrak
®System........................................4-6
All-Wheel Drive (AWD) System.........................4-9
Steering........................................................4-9
Off-Road Recovery.......................................4-11
Passing.......................................................4-11
Loss of Control.............................................4-12
Driving at Night............................................4-13Driving in Rain and on Wet Roads..................4-14
Before Leaving on a Long Trip.......................4-15
Highway Hypnosis........................................4-15
Hill and Mountain Roads................................4-16
Winter Driving..............................................4-17
If Your Vehicle is Stuck in Sand, Mud, Ice,
or Snow...................................................4-20
Rocking Your Vehicle to Get It Out.................4-21
Loading Your Vehicle....................................4-21
Towing..........................................................4-26
Towing Your Vehicle.....................................4-26
Recreational Vehicle Towing...........................4-26
Towing a Trailer...........................................4-30
Section 4 Driving Your Vehicle
4-1

Antilock Brake System (ABS)
Your vehicle has the Antilock Brake System (ABS), an
advanced electronic braking system that will help
prevent a braking skid.
When you start the engine and begin to drive away,
ABS will check itself. You might hear a momentary
motor or clicking noise while this test is going on, and
you might even notice that the brake pedal moves
a little. This is normal.
If there is a problem with
ABS, this warning light will
stay on. SeeAntilock
Brake System Warning
Light on page 3-48.
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 wheel.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, the computer keeps receiving updates
on wheel speed and controls braking pressure
accordingly.
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 the 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 antilock work for you. You might hear
the antilock pump or motor operate, and feel the
brake pedal pulsate, but this is normal.
4-5

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.
Panic Brake Assist
Your vehicle has a Panic Brake Assist feature designed
to assist the driver in stopping or decreasing vehicle
speed in emergency driving conditions. This feature uses
the Electronic Stability Control (ESC) hydraulic brake
control module to supplement the power brake system
under conditions where the driver has quickly and
forcefully applied the brake pedal in an attempt to quickly
stop or slow down the vehicle. The ESC hydraulic brake
control module increases brake pressure at each corner
of the vehicle until the Antilock Brake System (ABS)
activates. Minor brake pedal pulsations or pedal
movement during this time is normal and the driver
should continue to apply the brake pedal as the driving
situation dictates. The Panic Brake Assist feature will
automatically disengage when the brake pedal is
released or brake pedal pressure is quickly decreased.
StabiliTrak®System
Your vehicle has 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, SERVICE STABILITRAK. If you see these
conditions, 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 3-57.
4-6

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. It will activate and the
StabiliTrak
®light will ash if it senses that any of the
wheels are spinning or beginning to lose traction while
driving. If you turn off traction control, only the
brake-traction control portion of traction control will
work. The engine speed management will be disabled.
In this mode, engine power is not reduced automatically
and the driven wheels can spin more freely. This can
cause the brake-traction control to activate constantly.
Notice:If you allow the wheel(s) of one axle to spin
excessively while the StabiliTrak
®, ABS and brake
warning lights and the SERVICE STABILITRAK
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.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 StabiliTrak
®light will ash 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 3-12.
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/retailer for service.
4-8

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, the 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.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
want to slow down and adjust your driving to these
conditions. It is important to slow down on slippery
surfaces because stopping distance is 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 reducing vehicle speed by shifting to a lower
gear. Any sudden changes could cause the tires to slide.
You might 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 Antilock Brake System (ABS) helps
avoid only the braking skid.
4-12

StabiliTrak®improves your ability to accelerate when
driving on a slippery road. Even with StabiliTrak®, slow
down and adjust your driving to the road conditions.
Under certain conditions, you might want to turn
the traction control part of the StabiliTrak
®System off,
such as when driving through deep snow and loose
gravel, to help maintain vehicle motion at lower speeds.
SeeStabiliTrak
®System on page 4-6andIf Your
Vehicle is Stuck in Sand, Mud, Ice, or Snow on
page 4-20.
The Antilock Brake System (ABS) improves your
vehicle’s stability when you make a hard stop on a
slippery road. Even though you have ABS, begin
stopping sooner than you would on dry pavement. See
Antilock Brake System (ABS) on page 4-5.
Allow greater following distance on any slippery road.
Watch for slippery spots. The road might be ne until
you hit a spot that is covered with ice. On an
otherwise clear road, ice patches can appear in
shaded areas where the sun cannot reach, such as
around clumps of trees, behind buildings, or under
bridges. Sometimes the surface of a curve or an
overpass can remain icy when the surrounding roads
are clear. If you see a patch of ice ahead of you,
brake before you are on it. Try not to brake while you
are actually on the ice, and avoid sudden steering
maneuvers.
If You Are Caught in a Blizzard
If you are stopped by heavy snow, you could be in a
serious situation. You should probably stay with
your vehicle unless you know for sure that you are near
help and you can hike through the snow. Here are
some things to do to summon help and keep yourself
and your passengers safe:
Turn on the hazard warning ashers.
Tie a red cloth to your vehicle to alert police that
you have been stopped by the snow.
Put on extra clothing or wrap a blanket around you.
If you do not have blankets or extra clothing, make
body insulators from newspapers, burlap bags,
rags, oor mats — anything you can wrap around
yourself or tuck under your clothing to keep warm.
4-18