2010 GMC ACADIA brake

Driving and Operating 9-15
{WARNING
Things you put inside your
vehicle can strike and injure
people in a sudden stop or
turn, or in a crash.
.Put things in the cargo
area of your vehicle. Try to
spread the weight evenly.
.Never stack heavier
things, like suitcases,
inside the vehicle so that
some of them are above
the tops of the seats.
.Do not leave an
unsecured child restraint
in your vehicle.
.When you carry something
inside the vehicle, secure
it whenever you can.
.Do not leave a seat folded
down unless you need to.
Starting and
Operating
New Vehicle Break-In
Notice: The vehicle does not
need an elaborate break-in. But it
will perform better in the long run
if you follow these guidelines:
.If you have all-wheel drive,
keep your speed at 88 km/h
(55 mph) or less for the first
805 km (500 miles).
.Do not drive at any one
constant speed, fast or slow,
for the first 805 km
(500 miles). Do not make
full-throttle starts. Avoid
downshifting to brake or
slow the vehicle.
.Avoid making hard stops for
the first 322 km (200 miles) or
so. During this time the new
brake linings are not yet
broken in. Hard stops with
new linings can mean
premature wear and earlier
replacement. Follow this
breaking-in guideline every
time you get new brake
linings.
.Do not tow a trailer during
break-in. See Driving
Characteristics and Towing
Tips
on page 9‑44for the
trailer towing capabilities of
your vehicle and more
information.
Following break-in, engine speed
and load can be gradually
increased.

9-16 Driving and Operating
Ignition Positions
The ignition switch has four different
positions.
In order to shift out of P (Park), the
ignition must be in ON/RUN or ACC/
ACCESSORY and the brake pedal
must be applied.Notice:
Using a tool to force the
key to turn in the ignition could
cause damage to the switch or
break the key. Use the correct
key, make sure it is all the way in,
and turn it only with your hand.
If the key cannot be turned by
hand, see your dealer/retailer.
((LOCK/OFF): This position locks
the ignition and transmission. The
key can be removed in LOCK/OFF.
The shift lever must be in P (Park)
to turn the ignition switch to
LOCK/OFF.
The steering can bind with the
wheels turned off center. If this
happens, move the steering wheel
from right to left while turning the
key to ACC/ACCESSORY. If this
doesn't work, then the vehicle needs
service.
ACC (ACC/ACCESSORY): This is
the position in which you can
operate the electrical accessories or items plugged into the accessory
power outlets. This position unlocks
the ignition and steering wheel. Use
this position if the vehicle must be
pushed or towed.
R(ON/RUN):
This position can be
used to operate the electrical
accessories and to display some
instrument panel warning and
indicator lights. The switch stays in
this position when the engine is
running. The transmission is also
unlocked in this position. If you
leave the key in the ACC/
ACCESSORY or ON/RUN position
with the engine off, the battery could
be drained. You may not be able to
start the vehicle if the battery is
allowed to drain for an extended
period of time.
/(START): This is the position
that starts the engine. When the
engine starts, release the key. The
ignition switch will return to ON/RUN
for driving.

Driving and Operating 9-19
4. Before starting the engine, besure to unplug and store the
cord as it was before to keep it
away from moving engine parts.
If you do not, it could be
damaged.
The length of time the heater should
remain plugged in depends on
several factors. Ask a dealer/retailer
in the area where you will be
parking the vehicle for the best
advice on this.
Shifting Into Park
{WARNING
It can be dangerous to get out of
the vehicle if the shift lever is not
fully in P (Park) with the parking
brake firmly set. The vehicle can
roll. If you have left the engine
running, the vehicle can move
suddenly. You or others could be
injured. To be sure the vehicle will
not move, even when you are on (Continued)
WARNING (Continued)
fairly level ground, use the steps
that follow. If you are pulling a
trailer, seeDriving Characteristics
and Towing Tips on page 9‑44.
1. Hold the brake pedal down and set the parking brake. See
Parking Brake
on page 9‑27for
more information.
2. Move the shift lever into P (Park) by holding in the button on the
shift lever and pushing the shift
lever all the way toward the front
of the vehicle.
3. Turn the ignition key to LOCK/OFF.
4. Remove the key and take it with you. If you can leave the vehicle
with the ignition key in your
hand, the vehicle is in P (Park).
Leaving the Vehicle with the
Engine Running
{WARNING
It can be dangerous to leave the
vehicle with the engine running.
The vehicle could move suddenly
if the shift lever is not fully in
P (Park) with the parking brake
firmly set. And, if you leave the
vehicle with the engine running, it
could overheat and even catch
fire. You or others could be
injured. Do not leave the vehicle
with the engine running.
If you have to leave the vehicle with
the engine running, be sure the
vehicle is in P (Park) and the
parking brake is firmly set before
you leave it. After you have moved
the shift lever into P (Park), hold the
regular brake pedal down. Then,
see if you can move the shift lever
away from P (Park) without first
pushing the button.

9-20 Driving and Operating
If you can, it means that the shift
lever was not fully locked in
P (Park).
Torque Lock
Torque lock is when the weight of
the vehicle puts too much force on
the parking pawl in the
transmission. This happens when
parking on a hill and shifting the
transmission into P (Park) is not
done properly and then it is difficult
to shift out of P (Park). To prevent
torque lock, set the parking brake
and then shift into P (Park). To find
out how, see“Shifting Into Park”
listed previously.
If torque lock does occur, your
vehicle may need to be pushed
uphill by another vehicle to relieve
the parking pawl pressure, so you
can shift out of P (Park).
Shifting Out of Park
The vehicle is equipped with an
electronic shift lock release system.
The shift lock release is
designed to:
.Prevent ignition key removal
unless the shift lever is in
P (Park) with the shift lever
button fully released, and
.Prevent movement of the shift
lever out of P (Park), unless the
ignition is in ON/RUN or ACC/
ACCESSORY and the regular
brake pedal is applied.
The shift lock release is always
functional except in the case of an
uncharged or low voltage (less than
9 volt) battery.
If the vehicle has an uncharged
battery or a battery with low voltage,
try charging or jump starting the
battery. See Jump Starting
on
page 10‑78for more information. To shift out of P (Park):
1. Apply the brake pedal.
2. Press the shift lever button.
3. Move the shift lever to the
desired position.
If you still are unable to shift out of
P (Park):
1. Fully release the shift lever button.
2. While holding down the brake pedal, press the shift lever
button again.
3. Move the shift lever to the desired position.
If you still cannot move the shift
lever from P (Park), see your dealer/
retailer.

9-22 Driving and Operating
Running the Vehicle
While Parked
It is better not to park with the
engine running. But if you ever have
to, here are some things to know.
{WARNING
Idling a vehicle in an enclosed
area with poor ventilation is
dangerous. Engine exhaust may
enter the vehicle. Engine exhaust
contains Carbon Monoxide (CO)
which cannot be seen or smelled.
It can cause unconsciousness
and even death. Never run the
engine in an enclosed area that
has no fresh air ventilation. For
more information, seeEngine
Exhaust on page 9‑21.
{WARNING
It can be dangerous to get out of
the vehicle if the automatic
transmission shift lever is not fully
in P (Park) with the parking brake
firmly set. The vehicle can roll. Do
not leave the vehicle when the
engine is running unless you
have to. If you have left the
engine running, the vehicle can
move suddenly. You or others
could be injured. To be sure the
vehicle will not move, even when
you are on fairly level ground,
always set the parking brake and
move the shift lever to P (Park).
Follow the proper steps to be sure
the vehicle will not move. See
Shifting Into Park on page 9‑19.
If parking on a hill and pulling a
trailer, see Driving Characteristics
and Towing Tips on page 9‑44.
Automatic
Transmission
The automatic transmission has a
shift lever located on the console
between the seats.
P (Park): This position locks the
front wheels. It is the best position
to use when starting the engine
because the vehicle cannot move
easily.

Driving and Operating 9-23
{WARNING
It is dangerous to get out of the
vehicle if the shift lever is not fully
in P (Park) with the parking brake
firmly set. The vehicle can roll.
Do not leave the vehicle when the
engine is running unless you
have to. If you have left the
engine running, the vehicle can
move suddenly. You or others
could be injured. To be sure the
vehicle will not move, even when
you are on fairly level ground,
always set the parking brake and
move the shift lever to P (Park).
SeeShifting Into Park
on
page 9‑19
. If you are pulling a
trailer, see Driving Characteristics
and Towing Tips on page 9‑44.
Make sure the shift lever is fully in
P (Park) before starting the engine.
The vehicle has an automatic
transmission shift lock control system. You must fully apply the
regular brake first and then press
the shift lever button before shifting
from P (Park) when the ignition key
is in ON/RUN. If you cannot shift out
of P (Park), ease pressure on the
shift lever, then push the shift lever
all the way into P (Park) as you
maintain brake application. Then
press the shift lever button and
move the shift lever into another
gear. See
Shifting Out of Park
on
page 9‑20.
R (Reverse): Use this gear to
back up.
Notice: Shifting to R (Reverse)
while the vehicle is moving
forward could damage the
transmission. The repairs would
not be covered by the vehicle
warranty. Shift to R (Reverse) only
after the vehicle is stopped.
To rock the vehicle back and forth to
get out of snow, ice or sand without
damaging the transmission, see If
the Vehicle is Stuck on page 9‑10. N (Neutral):
In this position, the
engine does not connect with the
wheels. To restart the engine when
the vehicle is already moving, use
N (Neutral) only. Also, use
N (Neutral) when the vehicle is
being towed.
{WARNING
Shifting into a drive gear while the
engine is running at high speed is
dangerous. Unless your foot is
firmly on the brake pedal, the
vehicle could move very rapidly.
You could lose control and hit
people or objects. Do not shift
into a drive gear while the engine
is running at high speed.
Notice: Shifting out of P (Park) or
N (Neutral) with the engine
running at high speed may
damage the transmission. The
repairs would not be covered by
the vehicle warranty. Be sure the
engine is not running at high
speed when shifting the vehicle.

Driving and Operating 9-25
Automatic Engine Grade braking is
not available when the ERS is
active. It is available in D (Drive) for
both normal and Tow/Haul mode.
While using the ERS, cruise control
and the tow/haul mode can be used.
See Tow/Haul Mode following.
Tow/Haul Mode
_
(Tow/Haul):The vehicle may
have a Tow/Haul mode.
The button is located on the
instrument panel under the climate
controls.
Push the button to activate the
system. Push it again to deactivate
the system. You can use this feature
to assist when towing or hauling a
heavy load.
When Tow/Haul is activated the
Tow/Haul symbol will come on the
instrument panel cluster. See “Tow/
Haul Mode” underDriving
Characteristics and Towing Tips
on
page 9‑44for more information.
Automatic Engine Grade
Braking
Automatic Engine Grade Braking
assists when driving on a downhill
grade. It maintains vehicle speed by
automatically implementing a shift
schedule that uses the engine and
the transmission to slow the vehicle.
The system will automatically
command downshifts to reduce
vehicle speed, until the brake pedal
is no longer being pressed.
While in the Electronic Range
Select (ERS) mode, grade braking
is deactivated, allowing the driver to
select a range and limiting the
highest gear available. Grade
braking is available for normal
driving and in Tow/Haul mode.
See Automatic Transmission
on
page 9‑22.
Drive Systems
All-Wheel Drive
With this feature, engine power is
always sent to all four wheels. It is
fully automatic, and adjusts itself as
needed for road conditions.
When using a compact spare tire on
an AWD vehicle, the system
automatically detects the compact
spare and disables AWD. To restore
AWD operation and prevent
excessive wear on system, replace
the compact spare with a full-size
tire as soon as possible. See
Compact Spare Tire
on page 10‑77for more information.

9-26 Driving and Operating
Brakes
Antilock Brake
System (ABS)
This vehicle has the Antilock Brake
System (ABS), an advanced
electronic braking system that helps
prevent a braking skid.
When the engine is started and the
vehicle begins to drive away, ABS
checks itself. A momentary motor or
clicking noise might be heard while
this test is going on, and it might
even be noticed that the brake
pedal moves a little. This is normal.
If there is a problem with ABS, this
warning light stays on. SeeAntilock
Brake System (ABS) Warning Light
on page 5‑19. If driving safely on a wet road and it
becomes necessary to slam on the
brakes and continue braking to
avoid a sudden obstacle, a
computer senses that the 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
to each wheel, as required, faster
than any driver could. This can help
the driver steer around the obstacle
while braking hard.
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 firmly and let
ABS work. The ABS pump or motor
might be heard operating, 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.