2007 GMC ACADIA Owner's Manual

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 232.
The StabiliTrak
®light
will ash on the
instrument panel cluster
when the system is
both on and activated.
You may also feel or hear the system 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.
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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. Your 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, you may still hear system noises as a result
of the brake-traction control coming on.
It is recommended to leave the system on for
normal driving conditions, 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 Your Vehicle is Stuck
in Sand, Mud, Ice, or Snow on page 360.
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.
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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 180.
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.
All-Wheel Drive (AWD) System
If your 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 front axle. It is fully automatic, and
adjusts itself as needed for road conditions.
When using a compact spare tire on your 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 clutch in your AWD system, replace the
compact spare with a full-size tire as soon as
possible. SeeCompact Spare Tire on page 477
for more information.
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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
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 the 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.
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.
SeeStabiliTrak
®System on page 337.
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
the front wheels are straight ahead.
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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.
Adding non-dealer/non-retailer accessories can
affect your vehicle’s performance. SeeAccessories
and Modifications on page 385.
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 the brakes. SeeBraking
on page 334. 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.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.
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Off-Road Recovery
You may nd that your vehicle’s 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 nothingin 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 the steering
wheel to go straight down the roadway.
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.
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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.
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Check your vehicle’s 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
vehicle’s inside mirror, activate the right lane
change signal and move back into the
right lane. Remember that an outside convex
mirror makes the vehicle you just passed
seem 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 might 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.
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