2007 GMC ACADIA brake

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 anti-lock work for you.
You might hear the anti-lock pump or motor
operate, and feel the brake pedal pulsate, but this
is normal.
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.
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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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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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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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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 Anti-Lock Brake System (ABS)
helps avoid only the braking skid.
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And, if the tires do not have much tread left, you
get even less traction. It is always wise to go
slower and be cautious if rain starts to fall while
you are driving. The surface may get wet suddenly
when your reexes are tuned for driving on dry
pavement.
The heavier the rain, the harder it is to see.
Even if the windshield wiper blades are in good
shape, a heavy rain can make it harder to see road
signs and traffic signals, pavement markings,
the edge of the road, and even people walking.
It is wise to keep windshield wiping equipment in
good shape and keep the windshield washer
uid reservoir lled with washer uid. Replace
windshield wiper inserts when they show signs of
streaking or missing areas on the windshield,
or when strips of rubber start to separate from
the inserts.
{CAUTION:
Wet brakes can cause accidents. They
may not work as well in a quick stop and
may cause pulling to one side. You could
lose control of the vehicle.
After driving through a large puddle of
water or a car wash, apply the brake pedal
lightly until the brakes work normally.
Driving too fast through large water puddles or
even going through some car washes can cause
problems, too. The water may affect the brakes.
Try to avoid puddles. But if you cannot, try to slow
down before you hit them.
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Hill and Mountain Roads
Driving on steep hills or mountains is different
from driving in at or rolling terrain.If you drive regularly in steep country, or if you are
planning to visit there, here are some tips that
can make your trips safer and more enjoyable.
Keep your vehicle in good shape. Check
all uid levels and also the brakes, tires,
cooling system, and transmission. These parts
can work hard on mountain roads.
{CAUTION:
If you do not shift down, the brakes 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. Shift down to let the engine assist
the brakes on a steep downhill slope.
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