
GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-12146149) - 2019 - crc - 7/30/18
Driving and Operating 225
.The outside temperature is not
in the required operating range.
. The vehicle is in any gear other
than D (Drive).
. Tow/Haul Mode or other driver
modes have been selected.
. The vehicle is on a steep hill or
grade.
. The driver door has been
opened or driver seat belt has
been unbuckled.
. The hood has been opened.
. The Auto Stop has reached the
maximum allowed time.
Engine Heater
The engine heater can provide
easier starting and better fuel
economy during engine warm-up in
cold weather conditions at or below
0 °F (−18 °C). Vehicles with an
engine heater should be plugged in
at least four hours before starting.
Some models may have an internal
thermostat in the cord which will
prevent engine heater operation at
temperatures above 0 °F (−18 °C).
{Warning
Do not plug in the engine block
heater while the vehicle is parked
in a garage or under a carport.
Property damage or personal
injury may result. Always park the
vehicle in a clear open area away
from buildings or structures.
To Use the Engine Heater
1. Turn off the engine.
2. Open the hood and unwrap the
electrical cord. The bundled
cord is on the driver side of the
engine compartment, in front of
the battery. See Engine
Compartment Overview 0288.
Check the heater cord for
damage. If it is damaged, do
not use it. See your dealer for
a replacement. Inspect the
cord for damage yearly.
3. Plug the cord into a normal, grounded 110-volt AC outlet.
{Warning
Improper use of the heater cord
or an extension cord can damage
the cord and may result in
overheating and fire.
. Plug the cord into a
three-prong electrical utility
receptacle that is protected
by a ground fault detection
(Continued)

GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-12146149) - 2019 - crc - 7/30/18
226 Driving and Operating
Warning (Continued)
function. An ungrounded
outlet could cause an
electric shock.
. Use a weatherproof,
heavy-duty, 15 amp-rated
extension cord if needed.
Failure to use the
recommended extension
cord in good operating
condition, or using a
damaged heater or
extension cord, could make
it overheat and cause a fire,
property damage, electric
shock, and injury.
. Do not operate the vehicle
with the heater cord
permanently attached to the
(Continued)
Warning (Continued)
vehicle. Possible heater
cord and thermostat
damage could occur.
. While in use, do not let the
heater cord touch vehicle
parts or sharp edges. Never
close the hood on the
heater cord.
. Before starting the vehicle,
unplug the cord, reattach
the cover to the plug, and
securely fasten the cord.
Keep the cord away from
any moving parts.
4. Before starting the engine, be sure 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 in the
area where you will be parking the
vehicle for the best advice on this.
Retained Accessory
Power (RAP)
Some vehicle accessories may be
used after the ignition is turned off.
The power windows and sunroof,
if equipped, will continue to work for
up to 10 minutes or until any door is
opened.
The infotainment system will
continue to work for 10 minutes,
until the driver door is opened,
or until the ignition is turned on or
placed in ACC/ACCESSORY.
Shifting Into Park
1. Hold the brake pedal down and set the parking brake. See
Electric Parking Brake 0234.
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 off.

GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-12146149) - 2019 - crc - 7/30/18
Driving and Operating 227
Leaving the Vehicle with the
Engine Running
{Warning
It can be dangerous to leave the
vehicle with the engine running.
It could overheat and catch fire.
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. 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.
If you are towing a trailer, see
Driving Characteristics and
Towing Tips 0271. 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 0356 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.

GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-12146149) - 2019 - crc - 7/30/18
228 Driving and Operating
4. Move the shift lever to thedesired 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.
Parking over Things
That Burn
{Warning
Things that can burn could touch
hot exhaust parts under the
vehicle and ignite. Do not park
over papers, leaves, dry grass,
or other things that can burn.
Active Fuel Management
This vehicle's engine may be
equipped with Active Fuel
Management, which allows the
engine to operate on either all of its
cylinders, or in reduced cylinder
operation, depending on the driving
conditions.
When less power is required, such
as cruising at a constant vehicle
speed, the system will operate in
reduced cylinder operation mode,
allowing the vehicle to achieve
better fuel economy. When greater
power demands are required, such
as accelerating from a stop,
passing, or merging onto a freeway,
the system will maintain full-cylinder
operation.
If the vehicle has an Active Fuel
Management indicator, see Driver
Information Center (DIC) for more
information on using this display.
Extended Parking
It is best not to park with the vehicle
running. If the vehicle is left running,
be sure it will not move and there is
adequate ventilation.
See Shifting Into Park 0226 and
Engine Exhaust 0229.
If the vehicle is left parked and
running with the RKE transmitter
outside the vehicle, it will continue
to run for up to half an hour.
If the vehicle is left parked and
running with the RKE transmitter
inside the vehicle, it will continue to
run for up to an hour.
The vehicle could turn off sooner if it
is parked on a hill, due to lack of
available fuel.
The timer will reset if the vehicle is
taken out of P (Park) while it is
running.

GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-12146149) - 2019 - crc - 7/30/18
Driving and Operating 229
Engine Exhaust
{Warning
Engine exhaust contains carbon
monoxide (CO), which cannot be
seen or smelled. Exposure to CO
can cause unconsciousness and
even death.
Exhaust may enter the vehicle if:. The vehicle idles in areas
with poor ventilation
(parking garages, tunnels,
deep snow that may block
underbody airflow or tail
pipes).
. The exhaust smells or
sounds strange or different.
. The exhaust system leaks
due to corrosion or damage.
. The vehicle exhaust system
has been modified,
damaged, or improperly
repaired.
(Continued)
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 0229.
If parking on a hill and pulling a
trailer, see Driving Characteristics
and Towing Tips 0271.

GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-12146149) - 2019 - crc - 7/30/18
230 Driving and Operating
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)
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 0271.
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.

GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-12146149) - 2019 - crc - 7/30/18
Driving and Operating 231
{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.
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
0 232.
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.

GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-12146149) - 2019 - crc - 7/30/18
232 Driving and Operating
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.
To use this feature:1. Press the shift lever button and
move the shift lever to
L (Manual Mode).
2. Press + (Plus) or −(Minus) on
the shift lever to increase or
decrease the gear range
available.
When you shift from D (Drive) to
L (Manual Mode), the transmission
will shift to a pre-determined lower
gear range. The highest gear
available for this pre-determined
range is displayed next to the L in
the DIC.
See Driver Information Center (DIC)
(Base and Midlevel) 0145 orDriver
Information Center (DIC) (Uplevel)
0 148. The number displayed in the
DIC is the highest gear that the
transmission will be allowed to
operate in. This means that all
gears below that number are
available. For example, when
4 (Fourth) is shown next to the L,
1 (First) through 4 (Fourth) gears are
automatically shifted by the vehicle.
The transmission will not shift into
5 (Fifth) until the + (Plus) button is
used or you shift back into D (Drive). If the transmission is in 6 (Sixth)
gear when L (Manual Mode) is
selected, a downshift to 4 (Fourth)
will be commanded. If in 5 (Fifth)
through 2 (Second) a single
downshift will occur.
While in L (Manual Mode), the
transmission will prevent shifting to
a lower gear range if the engine
speed is too high. You have a brief
period of time to slow the vehicle.
If vehicle speed is not reduced
within the time allowed, the lower
gear range shift will not be
completed. You must further slow
the vehicle, then press
−(Minus) to
the desired lower gear range.
Automatic Engine Grade Braking is
not available when the ERS is
active. It is available in D (Drive) for
both normal driving and Tow/Haul
Mode. While using the ERS, cruise
control and the Tow/Haul Mode can
be used. See Tow/Haul Mode 0232.
Tow/Haul Mode
See Driver Mode Control 0239.