2009 GMC ACADIA brakes

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

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

Keep the windshield and all glass
on your vehicle clean — inside
and out.
Keep your eyes moving,
especially during turns or curves.
No one can see as well at night as
in the daytime. But, as we get
older, these differences increase.
A 50-year-old driver might need
at least twice as much light to see
the same thing at night as a
20-year-old.
Driving in Rain and on
Wet Roads
Rain and wet roads can reduce
vehicle traction and affect your
ability to stop and accelerate.
Always drive slower in these types
of driving conditions and avoid
driving through large puddles and
deep-standing or owing water.
{CAUTION
Wet brakes can cause crashes.
They might not work as well in a
quick stop and could cause
pulling to one side. You could
lose control of the vehicle.
After driving through a large
puddle of water or a car/vehicle
wash, lightly apply the brake
pedal until the brakes work
normally.
Flowing or rushing water creates
strong forces. Driving through
owing water could cause your
vehicle to be carried away. If this
happens, you and other vehicle
occupants could drown. Do not
ignore police warnings and be
very cautious about trying to drive
through owing water.
Hydroplaning
Hydroplaning is dangerous. Water
can build up under your vehicle’s
tires so they actually ride on
the water. This can happen if the
road is wet enough and you
are going fast enough. When your
vehicle is hydroplaning, it has little or
no contact with the road.
There is no hard and fast rule about
hydroplaning. The best advice is
to slow down when the road is wet.
Other Rainy Weather Tips
Besides slowing down, other wet
weather driving tips include:
Allow extra following distance.
Pass with caution.
Keep windshield wiping
equipment in good shape.
Keep the windshield washer uid
reservoir lled.
Have good tires with proper tread
depth. SeeTires on page 5-35.
Turn off cruise control.
Driving Your Vehicle 4-11

Before Leaving on a
Long Trip
To prepare your vehicle for a long
trip, consider having it serviced
by your dealer/retailer before
departing.
Things to check on your own
include:
Windshield Washer Fluid:
Reservoir full? Windows
clean — inside and outside?
Wiper Blades:In good shape?
Fuel, Engine Oil, Other Fluids:All
levels checked?
Lamps:Do they all work and are
lenses clean?
Tires:Are treads good? Are tires
inated to recommended
pressure?
Weather and Maps:Safe to
travel? Have up-to-date maps?
Highway Hypnosis
Always be alert and pay attention
to your surroundings while driving.
If you become tired or sleepy,
nd a safe place to park your
vehicle and rest.
Other driving tips include:
Keep the vehicle well ventilated.
Keep interior temperature cool.
Keep your eyes moving — scan
the road ahead and to the sides.
Check the rearview mirror and
vehicle instruments often.
Hill and Mountain Roads
Driving on steep hills or through
mountains is different than driving
on at or rolling terrain. Tips for
driving in these conditions include:
Keep the vehicle serviced
and in good shape.
Check all uid levels and brakes,
tires, cooling system, and
transmission.
Going down steep or long hills,
shift to a lower gear.
{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.
4-12 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

Towing a Trailer
{CAUTION
The driver can lose control when
pulling a trailer if the correct
equipment is not used or the
vehicle is not driven properly.
For example, if the trailer is too
heavy, the brakes may not work
well — or even at all. The driver
and passengers could be
seriously injured. The vehicle may
also be damaged; the resulting
repairs would not be covered by
the vehicle warranty. Pull a trailer
only if all the steps in this section
have been followed. Ask your
dealer/retailer for advice and
information about towing a trailer
with the vehicle.
To identify the trailering capacity of
the vehicle, read the information
in “Weight of the Trailer” that
appears later in this section.Trailering is different than just
driving the vehicle by itself.
Trailering means changes in
handling, acceleration, braking,
durability and fuel economy.
Successful, safe trailering takes
correct equipment, and it has to be
used properly.
The following information has many
time-tested, important trailering
tips and safety rules. Many of these
are important for the safety of the
driver and the passengers. So
please read this section carefully
before pulling a trailer.
Load-pulling components such as
the engine, transmission, rear
axle, wheel assemblies and tires are
forced to work harder against the
drag of the added weight. The
engine is required to operate
at relatively higher speeds and
under greater loads, generating
extra heat. What’s more, the trailer
adds considerably to wind
resistance, increasing the pulling
requirements.
Pulling A Trailer
Here are some important points:
There are many different
laws, including speed limit
restrictions, having to do with
trailering. Make sure the rig will
be legal, not only where you
live but also where you will be
driving. A good source for
this information can be state or
provincial police.
Consider using a sway control.
See “Hitches” later in this section.
Do not tow a trailer at all during
the rst 500 miles (800 km) the
new vehicle is driven. The engine,
axle or other parts could be
damaged.
Then, during the rst 500 miles
(800 km) that a trailer is towed, do
not drive over 50 mph (80 km/h)
and do not make starts at full
throttle. This helps the engine and
other parts of the vehicle wear in
at the heavier loads.
4-24 Driving Your Vehicle