brake GMC ACADIA 2018 Owner's Guide

GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349114) - 2018 - crc - 9/21/17
Driving and Operating 227
Warning (Continued)
always set the parking brake and
move the shift lever to P (Park).
SeeShifting Into Park 0226.
If you are towing a trailer, see
Driving Characteristics and
Towing Tips 0270.
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
pressing the button.
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 movement of the shift lever
out of P (Park), unless the ignition is
on or in 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 - North
America 0351 for more information.
To shift out of P (Park):
1. Turn the ignition on.
2. Apply the brake pedal.
3. Press the shift lever button.
4. 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.

GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349114) - 2018 - crc - 9/21/17
Driving and Operating 229
Warning (Continued)
.There are holes or openings
in the vehicle body from
damage or aftermarket
modifications that are not
completely sealed.
If unusual fumes are detected or
if it is suspected that exhaust is
coming into the vehicle: . Drive it only with the
windows completely down.
. Have the vehicle repaired
immediately.
Never park the vehicle with the
engine running in an enclosed
area such as a garage or a
building that has no fresh air
ventilation.
Running the Vehicle
While Parked
It is better not to park with the
engine running.
If the vehicle is left with the engine
running, follow the proper steps to
be sure the vehicle will not move.
See Shifting Into Park 0226 and
Engine Exhaust 0228.
If parking on a hill and pulling a
trailer, see Driving Characteristics
and Towing Tips 0270.
Automatic
Transmission
P : This position locks the drive
wheels. Use P (Park) when starting
the engine because the vehicle
cannot move easily.
{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.
(Continued)

GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349114) - 2018 - crc - 9/21/17
230 Driving and Operating
Warning (Continued)
Do not leave the vehicle when the
engine is running. 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 0226 and
Driving Characteristics and
Towing Tips 0270.
Make sure the shift lever is fully in
P (Park) before starting the engine.
The vehicle has an automatic
transmission shift lock control
system. With the ignition on fully
apply the regular brake, then press
the button on the back of the shift
lever before shifting from P (Park).
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 0227.
R : Use this gear to back up.
Caution
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 0217.
N : 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.
{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.
Caution
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.

GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349114) - 2018 - crc - 9/21/17
Driving and Operating 231
Caution
A transmission hot message may
display if the automatic
transmission fluid is too hot.
Driving under this condition can
damage the vehicle. Stop and idle
the engine to cool the automatic
transmission fluid. This message
clears when the transmission fluid
has cooled sufficiently.
D : This position is for normal
driving. If more power is needed for
passing, press the accelerator
pedal down.
Caution
If the vehicle does not shift gears,
the transmission could be
damaged. Have the vehicle
serviced right away.
If the vehicle is stopped on a hill,
with your foot off the brake pedal,
the vehicle may roll. This is normal
and is due to the torque converter designed to improve fuel economy
and performance. Use the brake to
hold the vehicle on a hill. Do not use
the accelerator pedal.
L :
This position gives you access
to gear ranges. This provides more
engine braking but lower fuel
economy than D (Drive). You can
use it on very steep hills, or in deep
snow or mud. See Manual Mode
0 231.
Operating Modes : The
transmission may operate in a lower
gear than normal to improve vehicle
performance. The engine speed
may be higher and there may be an
increase in noise during the
following conditions:
. When climbing a grade.
. When driving downhill.
. When driving in hot
temperatures, or at high altitude.
Manual Mode
Electronic Range Select
(ERS) Mode
ERS mode allows you to choose the
top-gear limit of the transmission
and the vehicle's speed while
driving downhill or towing a trailer.
The vehicle has an electronic shift
position indicator within the
instrument cluster. When using the
ERS mode a number will display
next to the L, indicating the highest
gear available for the range
selected.

GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349114) - 2018 - crc - 9/21/17
Driving and Operating 233
Brakes
Antilock Brake
System (ABS)
This vehicle has an Antilock Brake
System (ABS), an advanced
electronic braking system that helps
prevent a braking skid.
When the vehicle begins to drive
away, ABS checks itself.
A momentary motor or clicking noise
may be heard while this test is going
on, and it may 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
0 140. 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 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
you 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. You may hear the ABS
pump or motor operating and feel
the brake pedal pulsate. This is
normal.
Braking in Emergencies
ABS allows you to steer and brake
at the same time. In many
emergencies, steering can help
more than even the very best
braking.
Electric Parking Brake

GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349114) - 2018 - crc - 9/21/17
234 Driving and Operating
The vehicle has an Electric Parking
Brake (EPB). The EPB can always
be activated, even if the ignition is
off. To prevent draining the battery,
avoid repeated cycles of the EPB
system when the engine is not
running.
The system has a
Yor PARK
Electric Parking Brake light, and a
8
Service Parking Brake light or
message.
See Electric Parking Brake Light
0 139 andService Electric Parking
Brake Light (Uplevel and Midlevel
Cluster Only) 0139.
Before leaving the vehicle, check for
the
Yor PARK light to ensure that
the parking brake is applied.
EPB Apply
To apply the EPB:
1. Be sure the vehicle is at a complete stop.
2. Press the EPB switch momentarily. The
Yor PARK light will flash and
then stay on once the EPB is fully
applied. If the
Yor PARK light
flashes continuously, then the EPB
is only partially applied or there is a
problem with the EPB. A DIC
message will display. Release the
EPB and try to apply it again. If the
light does not come on, or keeps
flashing, have the vehicle serviced.
Do not drive the vehicle if the
Yor
PARK light is flashing. See your
dealer. See Electric Parking Brake
Light 0139.
If the
8light or message is on,
press the EPB switch and hold it.
Continue to hold the switch until
the
Yor PARK light remains on.
If the
8light or message remains
on, see your dealer.
If the EPB is applied while the
vehicle is moving, the vehicle will
decelerate as long as the switch is
pressed. If the switch is pressed
until the vehicle comes to a stop,
the EPB will remain applied. The vehicle may automatically apply
the EPB in some situations when
the vehicle is not moving. This is
normal, and is done to periodically
check the correct operation of the
EPB system.
If the EPB fails to apply, block the
rear wheels to prevent vehicle
movement.
EPB Release
To release the EPB:
1. Turn the ignition on or to ACC/ ACCESSORY.
2. Apply and hold the brake pedal.
3. Press the EPB switch momentarily.
The EPB is released when the
Y
or PARK light is off.
If the
8light or message is on,
release the EPB by pressing and
holding the EPB switch. Continue to
hold the switch until the
Yor

GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349114) - 2018 - crc - 9/21/17
Driving and Operating 235
PARK light is off. If either light stays
on after release is attempted, see
your dealer.
Caution
Driving with the parking brake on
can overheat the brake system
and cause premature wear or
damage to brake system parts.
Make sure that the parking brake
is fully released and the brake
warning light is off before driving.
Automatic EPB Release
The EPB will automatically release if
the vehicle is running, placed into
gear, and an attempt is made to
drive away. Avoid rapid acceleration
when the EPB is applied, to
preserve parking brake lining life.
Brake Assist
The Brake Assist feature is
designed to assist the driver in
stopping or decreasing vehicle
speed in emergency driving
conditions. This feature uses thestability 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 pulsation 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.
Hill Start Assist (HSA)
Hill Start Assist (HSA) will activate
when the vehicle is stopped on a
moderate to steep grade to help
prevent it from rolling in an
unintended direction. After the brake
pedal has been released and before
the accelerator pedal has been
pressed, HSA uses braking
pressure to hold the vehicle
stationary. If HSA is holding the
vehicle, a DIC message displays.
HSA will not activate in a forward
drive gear when facing downhill,
or in R (Reverse) when facing uphill.
Select the duration of the HSA
feature through vehicle
personalization. See
”Extended Hill
Start Assist” under“Comfort and
Convenience” inVehicle
Personalization 0152. When
Standard Hold is selected, the
vehicle is held stationary for up to
two seconds after the brake pedal is
released. When Extended Hold is
selected, the vehicle is held
stationary for up to five minutes
after the brake pedal is released. In
either case, override the hold
feature by pressing the accelerator
pedal and attempting to drive away.
If Standard Hold is selected, it will
hold the vehicle for two seconds
unless the driver door is opened or
the driver seat belt is unbuckled
after releasing the brake pedal.

GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349114) - 2018 - crc - 9/21/17
236 Driving and Operating
If Extended Hold is selected, it will
hold the vehicle for five minutes
unless the driver door is opened
and the driver seat belt is unbuckled
prior to releasing the brake pedal.
When deactivated after five minutes,
or if it is deactivated when the driver
seat belt is unlatched or the driver
door is opened, the Electric Parking
Brake will engage to prevent vehicle
movement.Ride Control Systems
Traction Control/
Electronic Stability
Control
System Operation
The vehicle has a Traction Control
System (TCS) and StabiliTrak®, an
electronic stability control system.
These systems help limit wheel spin
and assist the driver in maintaining
control, especially on slippery road
conditions.
TCS activates if it senses that any
of the drive wheels are spinning or
beginning to lose traction. When this
happens, TCS applies the brakes to
the spinning wheels and reduces
engine power to limit wheel spin.
StabiliTrak activates when the
vehicle senses a difference between
the intended path and the direction
the vehicle is actually traveling.
StabiliTrak selectively applies
braking pressure to any one of the vehicle wheel brakes to assist the
driver in keeping the vehicle on the
intended path.
If cruise control is being used and
TCS or StabiliTrak begins to limit
wheel spin, cruise control will
disengage. Cruise control may be
turned back on when road
conditions allow. TCS and
StabiliTrak will automatically turn on
when cruise control is set.
Both systems come on
automatically when the vehicle is
started and begins to move. The
systems may be heard or felt while
they are operating or while
performing diagnostic checks. This
is normal and does not mean there
is a problem with the vehicle.
It is recommended to leave both
systems on for normal driving
conditions, but it may be necessary
to turn TCS off if the vehicle gets
stuck in sand, mud, ice, or snow.
See
If the Vehicle Is Stuck 0217
and “Turning the Systems Off and
On” later in this section.

GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349114) - 2018 - crc - 9/21/17
Driving and Operating 237
The indicator light for both systems
is in the instrument cluster. This
light will:
.Flash when TCS is limiting
wheel spin
. Flash when StabiliTrak is
activated
. Turn on and stay on when either
system is not working
If either system fails to turn on or to
activate, a message may display in
the Driver Information Center (DIC),
and
dcomes on and stays on to
indicate that the system is inactive
and is not assisting the driver in
maintaining control. The vehicle is
safe to drive, but driving should be
adjusted accordingly.
If
dcomes on and stays on:
1. Stop the vehicle. 2. Turn the engine off and wait
15 seconds.
3. Start the engine.
4. Drive the vehicle.
If
dcomes on and stays on, the
vehicle may need more time to
diagnose the problem. If the
condition persists, see your dealer.
Turning the Systems Off
and On
Caution
Do not repeatedly brake or
accelerate heavily when TCS is
off. The vehicle driveline could be
damaged.
To turn off only TCS, press and
release
g. The Traction Off lighti
displays in the instrument cluster
and a DIC message may display.
To turn TCS on again, press and
release
g. The Traction Off lighti
displayed in the instrument cluster
will turn off.
If TCS is limiting wheel spin when
g
is pressed, the system will not turn
off until the wheels stop spinning.
To turn off both TCS and StabiliTrak,
press and hold
guntil the Traction
Off light
iand StabiliTrak OFF light
gcome on and stay on in the
instrument cluster. A DIC message
may display.

GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349114) - 2018 - crc - 9/21/17
238 Driving and Operating
To turn TCS and StabiliTrak on
again, press and release
g. The
Traction Off light
iand StabiliTrak
OFF light
gin the instrument cluster
turn off.
Adding accessories can affect the
vehicle performance. See
Accessories and Modifications
0 281.
Hill Descent
Control (HDC)
If equipped, HDC can be used when
driving downhill. It sets and
maintains vehicle speed while
descending a very steep incline in a
forward or reverse gear.
The HDC switch is on the center
console, behind the transmission
shift lever.
Press
5to enable or disable HDC.
Vehicle speed must be below
50 km/h (31 mph).
A blinking HDC light indicates the
system is actively applying the
brakes to maintain vehicle speed.
HDC can maintain vehicle speeds
between 3 and 22 km/h (2 and
14 mph) on an incline greater than
or equal to a 10% grade.
When HDC is activated, the initial
HDC speed is set to the current
driving speed. It can be increased or
decreased by pressing the RES+ or
SET– steering wheel controls or by
applying the accelerator or brake
pedal. This adjusted speed
becomes the new set speed.
HDC will remain enabled between
22 and 60 km/h (14 and 37 mph);
however vehicle speed cannot be
set or maintained in this range.
It will automatically disable if the
vehicle speed is above 80 km/h (50 mph) or above 60 km/h
(37 mph) for at least 30 seconds.
Press
5again to re-enable HDC.
Driver Mode Control
If equipped, the Driver Mode Control
has the following Modes: Tour
(FWD), Sport, All-Wheel Drive
(AWD), Snow/Ice, Tow/Haul, and
Off-Road. Rotate the Driver Mode
Control knob on the center console
to make a mode selection. Continue
turning the knob through the
available modes. The selected
mode’s icon will light up on
the knob.
If the vehicle is in Tour (FWD) or
AWD, it will stay in that mode
through future ignition cycles. If the
vehicle is in any other mode, it will
revert back to Tour (FWD) when the
vehicle is restarted.