
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 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
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
240 Driving and Operating
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.
SeeAutomatic Transmission 0229.
7Off-Road (AWD Only) : Use
this mode for off-road recreational
driving. Choosing Off-Road Mode
also engages AWD Mode. For more
information on Off-Road Mode, see
Off-Road Driving 0209.
Cruise Control
{Warning
Cruise control can be dangerous
where you cannot drive safely at
a steady speed. Do not use
cruise control on winding roads or
in heavy traffic.
Cruise control can be dangerous
on slippery roads. On such roads,
fast changes in tire traction can
cause excessive wheel slip, and
you could lose control. Do not use
cruise control on slippery roads.
With cruise control, a speed of
about 40 km/h (25 mph) or more can
be maintained without keeping your
foot on the accelerator. Cruise
control does not work at speeds
below about 40 km/h (25 mph).
If the Traction Control System (TCS)
or StabiliTrak
®electronic stability
control system begins to limit wheel
spin while using cruise control, the
cruise control automatically disengages. See
Traction Control/
Electronic Stability Control 0236.
If a collision alert occurs when
cruise control is activated, cruise
control is disengaged. See Forward
Collision Alert (FCA) System 0256.
When road conditions allow the
cruise control to be safely used,
cruise control can be turned
back on.
Turning off the TCS or StabiliTrak
system will disengage the cruise
control.
If the brakes are applied, cruise
control disengages.

GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349114) - 2018 - crc - 9/21/17
Driving and Operating 243
conditions allow ACC to be safely
used, the ACC can be turned
back on.
Turning off the TCS or StabiliTrak
system will disengage the cruise
control.
{Warning
ACC has limited braking ability
and may not have time to slow
the vehicle down enough to avoid
a collision with another vehicle
you are following. This can occur
when vehicles suddenly slow or
stop ahead, or enter your lane.
Also see“Alerting the Driver” in
this section. Complete attention is
always required while driving and
you should be ready to take
action and apply the brakes. See
Defensive Driving 0207.
{Warning
ACC will not detect or brake for
children, pedestrians, animals,
or other objects.
Do not use ACC when:
. On winding and hilly roads
or when the sensors are
blocked by snow, ice, or dirt.
The system may not detect
a vehicle ahead. Keep the
entire front of the vehicle
clean.
. Visibility is low, such as in
fog, rain, or snow
conditions. ACC
performance is limited under
these conditions.
. On slippery roads where
fast changes in tire traction
can cause excessive
wheel slip.
J:Press to turn the system on or
off. The indicator turns white on the
instrument cluster when ACC is
turned on.
RES+ : Press briefly to resume the
previous set speed or to increase
vehicle speed if ACC is already
activated. To increase speed by
1 km/h (1 mph), press RES+ to the
first detent. To increase speed to the
next 5 km/h (5 mph) mark on the
speedometer, press RES+ to the
second detent.
SET– :Press briefly to set the
speed and activate ACC or to
decrease vehicle speed if ACC is

GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349114) - 2018 - crc - 9/21/17
244 Driving and Operating
already activated. To decrease
speed by 1 km/h (1 mph), press
SET−to the first detent. To
decrease speed to the next 5 km/h
(5 mph) mark on the speedometer,
press SET− to the second detent.
*:Press to disengage ACC
without erasing the selected set
speed.
[: Press to select a following gap
time (or distance) setting for ACC of
Far, Medium, or Near.
Switching Between ACC and
Regular Cruise Control
To switch between ACC and regular
cruise control, press and hold
*.
A Driver Information Display (DIC)
message displays. See Vehicle
Messages 0151.
ACC IndicatorRegular Cruise
Control Indicator When ACC is engaged, a green
]
indicator will be lit on the instrument
cluster. When the regular cruise
control is engaged, a green
J
indicator will be lit on the instrument
cluster.
When the vehicle is turned on, the
cruise control mode will be set to
the last mode used before the
vehicle was turned off.
{Warning
Always check the cruise control
indicator on the instrument cluster
to determine which mode cruise
control is in before using the
feature. If ACC is not active, the
vehicle will not automatically
brake for other vehicles, which
could cause an accident if the
brakes are not applied manually.
You and others could be seriously
injured or killed.
Setting Adaptive Cruise Control
If
Jis on when not in use, it could
get pressed and go into cruise when
not desired. Keep
Joff when
cruise is not being used.
Select the set speed desired for
cruise. This is the vehicle speed
when no vehicle is detected in
its path.
ACC will not set at a speed less
than 25 km/h (15 mph), although it
can be resumed when driving at
lower speeds.
To set ACC:
1. Press
J.
2. Get up to the desired speed.
3. Press and release SET–.
4. Remove foot from the accelerator.
After ACC is set, it may immediately
apply the brakes if a vehicle ahead
is detected closer than the selected
following gap.

GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349114) - 2018 - crc - 9/21/17
Driving and Operating 247
vehicle detected ahead. Consider
traffic and weather conditions when
selecting the following gap. The
range of selectable gaps may not be
appropriate for all drivers and
driving conditions.
Changing the gap setting
automatically changes the alert
timing sensitivity (Far, Medium,
or Near) for the Forward Collision
Alert (FCA) feature. SeeForward
Collision Alert (FCA) System 0256.
Alerting the Driver
If ACC is engaged, driver action
may be required when ACC cannot
apply sufficient braking because of
approaching a vehicle too rapidly.
When this condition occurs, six red
lights will flash on the windshield.
Either eight beeps will sound from
the front, or both sides of the Safety Alert Seat will pulse five times. See
“Collision/Detection Systems”
under
Vehicle Personalization 0152.
See Defensive Driving 0207.
Approaching and Following a
Vehicle
The vehicle ahead indicator is in the
instrument cluster.
The vehicle ahead indicator only
displays when a vehicle is detected
in your vehicle’s path moving in the
same direction.
If this symbol is not displaying, ACC
will not respond to or brake for
vehicles ahead.
ACC automatically slows the vehicle
down and adjusts vehicle speed to
follow the vehicle in front at the
selected follow gap. The vehicle
speed increases or decreases to follow the vehicle in front of you, but
will not exceed the set speed. It may
apply limited braking, if necessary.
When braking is active, the brake
lights will come on. The automatic
braking may feel or sound different
than if the brakes were applied
manually. This is normal.
Stationary or Very Slow-Moving
Objects
{Warning
ACC may not detect and react to
stopped or slow-moving vehicles
ahead of you. For example, the
system may not brake for a
vehicle it has never detected
moving. This can occur in
stop-and-go traffic or when a
vehicle suddenly appears due to
a vehicle ahead changing lanes.
Your vehicle may not stop and
could cause a crash. Use caution
when using ACC. Your complete
attention is always required while
(Continued)