2009 GMC ACADIA wheel

As the brakes are applied, the
computer keeps receiving updates
on wheel speed and controls braking
pressure accordingly.
Remember: ABS does not change
the time needed to get a foot
up to the brake pedal or always
decrease stopping distance. If you
get too close to the vehicle in
front of you, there will not be enough
time to apply the brakes if that
vehicle suddenly slows or stops.
Always leave enough room up
ahead to stop, even with ABS.
Using ABS
Do not pump the brakes. Just hold
the brake pedal down rmly and
let antilock work. The antilock pump
or motor operating might be
heard and the brake pedal might be
felt to pulsate, but this is normal.
Braking in Emergencies
ABS allows the driver to steer and
brake at the same time. In many
emergencies, steering can help more
than even the very best braking.
Brake Assist
This vehicle has a Brake Assist
feature designed to assist the driver
in stopping or decreasing vehicle
speed in emergency driving
conditions. This feature uses the
stability system 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
stability system hydraulic brake
control module increases brake
pressure at each corner of the
vehicle until the 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 Brake Assist feature will
automatically disengage when the
brake pedal is released or brake
pedal pressure is quickly decreased.
StabiliTrak®System
The 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 the vehicle and
begin to drive away, the system
performs several diagnostic checks
to ensure there are no problems. The
system may be heard or felt while it
is working. This is normal and does
not mean there is a problem with the
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.
Driving Your Vehicle 4-5

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 these
conditions are observed, 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), the vehicle should be
taken in for service. For more
information on the DIC messages,
seeDriver Information Center (DIC)
on page 3-46.
The StabiliTrak light will ash on the
instrument panel cluster when the
system is both on and activated.
The system may be heard or
felt while it is working; this is normal.The traction control disable button
is located on the instrument
panel below the climate controls.
The traction control part of
StabiliTrak can be turned off by
pressing and releasing the traction
control disable button.
Traction control can be turned on
by pressing and releasing the
traction control disable button if
not automatically shut off for any
other reason.
When the traction control system is
turned off, the StabiliTrak light and
the appropriate traction control off
message will be displayed on the
DIC to warn the driver. The vehicle
will still have brake-traction control
when traction control is off, but will
not be able to use the engine speed
management system. See “Traction
Control Operation” next for more
information.When the traction control system
has been turned off, system noises
may be heard and felt as a result
of the brake-traction control working.
It is recommended to leave the
system on for normal driving
conditions, but it may be necessary
to turn the system off if the
vehicle is stuck in sand, mud, ice or
snow, and you want to “rock” the
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 Your
Vehicle is Stuck in Sand, Mud,
Ice, or Snow on page 4-15.
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.
4-6 Driving Your Vehicle

The traction control system is
enabled automatically when the
vehicle is started. 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 traction control is
turned off, 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 the wheel(s) of one axle
is allowed to spin excessively
while the StabiliTrak, ABS and
brake warning lights and any
relevant DIC messages are
displayed, the transfer case could
be damaged. The repairs would
not be covered by the vehicle
warranty. Reduce engine power
and do not spin the wheel(s)
excessively while these lights
and messages 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, a
reduction in acceleration may be
noticed, or a noise or vibration may
be heard. This is normal.
If cruise control is being used when
the system activates, the StabiliTrak
light will ash and cruise control
will automatically disengage. Cruise
control may be reengaged when
road conditions allow. SeeCruise
Control on page 3-9.
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, see your
dealer/retailer for service.All-Wheel Drive (AWD)
System
If the vehicle has this feature,
engine power is sent to all four
wheels when extra traction is
needed. This is like four-wheel drive,
but there is no separate lever or
switch to engage or disengage the
axle. It is fully automatic, and
adjusts itself as needed for road
conditions.
When using a compact spare tire
on the AWD equipped vehicle,
the AWD system automatically
detects the presence of the compact
spare and the AWD is disabled.
To restore the AWD operation and
prevent excessive wear on the
AWD system, replace the compact
spare with a full-size tire as
soon as possible. SeeCompact
Spare Tire on page 5-81for more
information.
Driving Your Vehicle 4-7

Steering
Power Steering
If power steering assist is lost
because the engine stops or the
system is not functioning, the vehicle
can be steered but it will take
more effort.
Variable Effort Steering
If the vehicle has this steering
system, the system continuously
adjusts the effort felt when steering
at all vehicle speeds. It provides
ease when parking, yet a rm, solid
feel at highway speeds.
Steering Tips
It is important to take curves at a
reasonable speed.
Traction in a curve depends on the
condition of the tires and the
road surface, the angle at which the
curve is banked, and vehicle
speed. While in a curve, speed is
the one factor that can be controlled.If there is a need to reduce speed,
do it before entering the curve,
while the front wheels are straight.
Try to adjust the speed so you
can drive through the curve.
Maintain a reasonable, steady
speed. Wait to accelerate until 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.
These problems can be avoided
by braking — if you can stop in time.
But sometimes you cannot stop in
time because there is no room.
That is the time for evasive
action — steering around the
problem.The vehicle can perform very well in
emergencies like these. First,
apply the brakes. SeeBraking on
page 4-3. It is better to remove
as much speed as possible from a
collision. Then steer around the
problem, to the left or right
depending on the space available.
An emergency like this requires
close attention and a quick decision.
If holding the steering wheel at
the recommended 9 and 3 o’clock
positions, it can be turned a
full 180 degrees very quickly
without removing either hand.
4-8 Driving Your Vehicle

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
The vehicle’s right wheels can drop
off the edge of a road onto the
shoulder while 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 the vehicle straddles
the edge of the pavement. Turn
the steering wheel 3 to 5 inches,
8 to 13 cm, (about one-eighth turn)
until the right front tire contacts
the pavement edge. Then turn
the steering wheel to go straight
down the roadway.Passing
Passing another vehicle on a
two-lane road can be dangerous.
To reduce the risk of danger
while passing:
Look down the road, to the sides,
and to crossroads for situations
that might affect a successful
pass. If in doubt, wait.
Watch for traffic signs, pavement
markings, and lines that could
indicate a turn or an intersection.
Never cross a solid or
double-solid line on your
side of the lane.
Do not get too close to the vehicle
you want to pass. Doing so can
reduce your visibility.
Wait your turn to pass a slow
vehicle.
When you are being passed, ease
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.
Driving Your Vehicle 4-9

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 the 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.
If the 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, the
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,
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
the 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.
Driving at Night
Night driving is more dangerous than
day driving because some drivers
are likely to be impaired — by alcohol
or drugs, with night vision problems,
or by fatigue.
Night driving tips include:
Drive defensively.
Do not drink and drive.
Reduce headlamp glare by
adjusting the inside rearview
mirror.
Slow down and keep more space
between you and other vehicles
because headlamps can only
light up so much road ahead.
Watch for animals.
When tired, pull off the road.
Do not wear sunglasses.
Avoid staring directly into
approaching headlamps.
4-10 Driving Your Vehicle

{CAUTION
Coasting downhill in N (Neutral) or
with the ignition off is dangerous.
The brakes will have to do all the
work of slowing down and they
could get so hot that they would
not work well. You would then
have poor braking or even none
going down a hill. You could crash.
Always have the engine running
and the vehicle in gear when going
downhill.
Stay in your own lane. Do not
swing wide or cut across the
center of the road. Drive at
speeds that let you stay in your
own lane.
Top of hills: Be alert — something
could be in your lane (stalled car,
accident).
Pay attention to special road
signs (falling rocks area, winding
roads, long grades, passing or
no-passing zones) and take
appropriate action.
Winter Driving
Driving on Snow or Ice
Drive carefully when there is snow
or ice between the tires and the
road, creating less traction or
grip. Wet ice can occur at about
32°F (0°C) when freezing rain
begins to fall, resulting in even
less traction. Avoid driving on wet
ice or in freezing rain until roads
can be treated with salt or sand.
Drive with caution, whatever the
condition. Accelerate gently so
traction is not lost. Accelerating too
quickly causes the wheels to spin
and makes the surface under the
tires slick, so there is even less
traction.Try not to break the fragile traction.
If you accelerate too fast, the drive
wheels will spin and polish the
surface under the tires even more.
TheStabiliTrak
®System on page 4-5
improves the ability to accelerate on
slippery roads, but slow down and
adjust your driving to the road
conditions. When driving through
deep snow, turn off the traction
control part of the StabiliTrak
®
System to help maintain vehicle
motion at lower speeds.
TheAntilock Brake System (ABS)
on page 4-4improves vehicle
stability during hard stops on a
slippery roads, but apply the brakes
sooner than when on dry pavement.
Allow greater following distance
on any slippery road and watch
for slippery spots. Icy patches
can occur on otherwise clear
roads in shaded areas.
Driving Your Vehicle 4-13

To save fuel, run the engine for only
short periods as needed to warm the
vehicle and then shut the engine off
and close the window most of the
way to save heat. Repeat this until
help arrives but only when you feel
really uncomfortable from the cold.
Moving about to keep warm also
helps.
If it takes some time for help to
arrive, now and then when you run
the engine, push the accelerator
pedal slightly so the engine runs
faster than the idle speed. This
keeps the battery charged to restart
the vehicle and to signal for help with
the headlamps. Do this as little as
possible to save fuel.
If Your Vehicle is
Stuck in Sand, Mud, Ice,
or Snow
Slowly and cautiously spin the
wheels to free the vehicle when
stuck in sand, mud, ice, or snow.
SeeRocking Your Vehicle to Get It
Out on page 4-15.If the vehicle has a traction system,
it can often help to free a stuck
vehicle. Refer to the vehicle’s
traction system in the Index. If stuck
too severely for the traction
system to free the vehicle, turn the
traction system off and use the
rocking method.
{CAUTION
If you let your vehicle’s tires spin
at high speed, they can explode,
and you or others could be
injured. The vehicle can overheat,
causing an engine compartment
re or other damage. Spin the
wheels as little as possible and
avoid going above 35 mph
(55 km/h) as shown on the
speedometer.
For information about using tire
chains on the vehicle, seeTire
Chains on page 5-54.
Rocking Your Vehicle to
Get It Out
Turn the steering wheel left and
right to clear the area around
the front wheels. Turn off any
traction or stability system. Shift
back and forth between R (Reverse)
and a forward gear, spinning the
wheels as little as possible. To
prevent transmission wear, wait until
the wheels stop spinning before
shifting gears. Release the
accelerator pedal while shifting, and
press lightly on the accelerator
pedal when the transmission is in
gear. Slowly spinning the wheels in
the forward and reverse directions
causes a rocking motion that
could free the vehicle. If that does
not get the vehicle out after a
few tries, it might need to be towed
out. If the vehicle does need to
be towed out, seeTowing Your
Vehicle on page 4-20.
Driving Your Vehicle 4-15