2021 GMC ACADIA engine

GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-14608671) - 2021 - CRC - 10/26/20
Driving and Operating 227
may be turned back on when road
conditions allow. TCS and StabiliTrak/ESC 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. SeeIf the
Vehicle Is Stuck 0209 and“Turning the
Systems Off and On” later in this section.
The indicator light for both systems is in the
instrument cluster. This light:
.Will flash when TCS is limiting wheel spin
.Will flash when StabiliTrak/ESC is
activated
.Will turn on and stay on when either
system is not working
.May flash when ABS is active
If either system fails to turn on or to
activate, a message may display in the
Driver Information Center (DIC), and
d
comes 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 light
idisplays in the
instrument cluster and a DIC message may
display.
To turn TCS on again, press and release
g.
The Traction Off light
idisplayed in the
instrument cluster will turn off.

GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-14608671) - 2021 - CRC - 10/26/20
Driving and Operating 229
Driver Mode Control Knob (AWD)
Driver Mode Control Knob (FWD)
5orqTour (FWD) :Vehicle is in Tour
(FWD) Mode. Use this mode during normal
driving conditions. See Driving for Better Fuel
Economy 0200. Tour (FWD) Mode operates
in Front-Wheel Drive to improve fuel
economy.
8Sport : Sport Mode improves vehicle
handling and acceleration on dry pavement.
When active, Sport Mode modifies steering
efforts, transmission shifting, AWD torque,
and suspension tuning (when properly
equipped). For AWD vehicles, choosing Sport
Mode also engages AWD Mode.
The Performance Algorithm Liftfoot (PAL)
feature is enabled in Sport Mode. PAL allows
the transmission to hold the current gear
after a quick release of a heavily applied
accelerator pedal. This provides greater
engine braking and enhanced vehicle control.
When PAL is activated, there may be an
additional green gear symbol which appears
in the instrument cluster display. See Gear
Shifting Light 0110.
4AWD (AWD Only) : AWD Mode
provides drive torque to all four wheels.
Select AWD to improve traction and control
on slippery road surfaces, such as gravel,
sand, wet pavement, snow, and ice. When in AWD Mode, the AWD Mode indicator will be
on. The AWD Mode will stay selected until
the mode is changed.
AWD is active in AWD, Sport, Tow/Haul, and
Off-Road Modes.
Sport, Tow/Haul, and Off-Road Modes are
cancelled with each ignition cycle and will
return to Tour (FWD) Mode.
When using a compact spare tire on an
AWD vehicle, the system automatically
detects the compact spare and reduces AWD
performance to protect the system. To
restore full AWD operation and prevent
excessive wear on the system, replace the
compact spare with a full-size tire as soon as
possible. See
Compact Spare Tire 0331.
6Snow/Ice (FWD Only) : Snow/Ice Mode
improves vehicle acceleration on snow and
ice covered roads.
_Tow/Haul : This feature can assist
when towing or hauling a heavy load. Use
this mode to assist in maintaining desired
vehicle speeds when driving on downhill
grades by using the engine and
transmission. For AWD vehicles, choosing
Tow/Haul Mode also engages AWD mode.
See Driving Characteristics and Towing Tips
0 256.

GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-14608671) - 2021 - CRC - 10/26/20
230 Driving and Operating
Automatic Engine Grade Braking
Automatic Engine Grade Braking assists
when driving downhill. It maintains vehicle
speed by automatically implementing a shift
pattern that uses the engine and the
transmission to slow the vehicle. The system
will automatically command downshifts to
reduce vehicle speed. The normal shift
pattern will return once the vehicle is on a
low grade or when the accelerator pedal is
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.
SeeAutomatic Transmission 0220.
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 0203.
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 StabiliTrak/Electronic Stability Control
(ESC) system begins to limit wheel spin
while using cruise control, the cruise control
automatically disengages. See Traction
Control/Electronic Stability Control 0226.
If a collision alert occurs when cruise control
is activated, cruise control is disengaged. See
Forward Collision Alert (FCA) System 0245. When road conditions allow the cruise
control to be safely used, cruise control can
be turned back on.
Turning off the TCS or StabiliTrak/ESC
system will disengage the cruise control.
If the brakes are applied, cruise control
disengages.
J:
Press to turn the system on and off.
A white indicator appears in the instrument
cluster when cruise is turned on.
RES+ : If there is a set speed in memory,
press briefly to resume to that speed or
press and hold to accelerate. If the cruise
control is already active, use to increase
vehicle speed.

GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-14608671) - 2021 - CRC - 10/26/20
Driving and Operating 253
Ais green if LKA is ready to assist. LKA
may assist by gently turning the steering
wheel if the vehicle approaches a detected
lane marking.
Ais amber when
assisting. It may also provide a Lane
Departure Warning (LDW) alert by flashing
Aamber if the vehicle crosses a
detected lane marking. Additionally, there
may be three beeps on the right or left,
depending on the lane departure direction.
Take Steering
The LKA system does not continuously steer
the vehicle. If LKA does not detect active
driver steering, an alert and chime may be
provided. Steer the vehicle to dismiss. LKA
may become temporarily unavailable after
repeated take steering alerts.
When the System Does Not Seem to
Work Properly
The system performance may be
affected by:
.Close vehicles ahead.
.Sudden lighting changes, such as when
driving through tunnels.
.Banked roads.
.Roads with poor lane markings, such as
two-lane roads. If the LKA system is not functioning
properly when lane markings are clearly
visible, cleaning the windshield may help.
A camera blocked message may display if
the camera is blocked. Some driver
assistance systems may have reduced
performance or not work at all. An LKA or
LDW unavailable message may display if the
systems are temporarily unavailable. This
message could be due to a blocked camera.
The LKA system does not need service. Clean
the outside of the windshield behind the
rearview mirror.
LKA assistance and/or LDW alerts may occur
due to tar marks, shadows, cracks in the
road, temporary or construction lane
markings, or other road imperfections. This
is normal system operation; the vehicle does
not need service. Turn LKA off if these
conditions continue.
Fuel
Top Tier Fuel
GM recommends the use of TOP TIER
Detergent Gasoline to keep the engine clean,
reduce engine deposits, and maintain
optimal vehicle performance. Look for the
TOP TIER Logo or see www.toptiergas.com
for a list of TOP TIER Detergent Gasoline
marketers and applicable countries.
Recommended Fuel
Use regular unleaded gasoline meeting
ASTM specification D4814 with a posted
octane rating of 87
—(R+M)/2 —or higher.
Do not use gasoline with a posted octane
rating of less than 87, as this may cause
engine knock and will lower fuel economy.

GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-14608671) - 2021 - CRC - 10/26/20
254 Driving and Operating
Do not use any fuel labeled E85 or FlexFuel.
Do not use gasoline with ethanol levels
greater than 15% by volume.
Prohibited Fuels
Caution
Do not use fuels with any of the
following conditions; doing so may
damage the vehicle and void its
warranty:
.For vehicles that are not FlexFuel, fuel
labeled greater than 15% ethanol by
volume, such as mid-level ethanol
blends (16–50% ethanol), E85,
or FlexFuel.
.Fuel with any amount of methanol,
methylal, ferrocene, and aniline. These
fuels can corrode metal fuel system
parts or damage plastic and rubber
parts.
.Fuel containing metals such as
methylcyclopentadienyl manganese
tricarbonyl (MMT), which can damage
the emissions control system and
spark plugs.
(Continued)
Caution (Continued)
.Fuel with a posted octane rating of
less than the recommended fuel. Using
this fuel will lower fuel economy and
performance, and may decrease the
life of the emissions catalyst.
Fuels in Foreign Countries
The U.S., Canada, and Mexico post fuel
octane ratings in anti-knock index (AKI). For
fuel not to use in a foreign country, see
Prohibited Fuels0254.
Fuel Additives
TOP TIER Detergent Gasoline is highly
recommended for use with your vehicle.
If your country does not have TOP TIER
Detergent Gasoline, add ACDelco Fuel
System Treatment Plus−Gasoline to the
vehicle’s gasoline fuel tank at every oil
change or 15 000 km (9,000 mi), whichever
occurs first. TOP TIER Detergent Gasoline and
ACDelco Fuel System Treatment Plus
−Gasoline will help keep your vehicle’s
engine fuel deposit free and performing
optimally.
Filling the Tank
An arrow on the fuel gauge indicates which
side of the vehicle the fuel door is on. See
Fuel Gauge 0102.
{Warning
Fuel vapors and fuel fires burn violently
and can cause injury or death.
Follow these guidelines to help avoid
injuries to you and others:
.Read and follow all the instructions on
the fuel pump island.
.Turn off the engine when refueling.
.Keep sparks, flames, and smoking
materials away from fuel.
.Do not leave the fuel pump
unattended.
.Avoid using electronic devices while
refueling.
.Do not re-enter the vehicle while
pumping fuel.
.Keep children away from the fuel
pump and never let children
pump fuel.
(Continued)

GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-14608671) - 2021 - CRC - 10/26/20
Driving and Operating 255
Warning (Continued)
.Before touching the fill nozzle, touch a
metallic object to discharge static
electricity from your body.
.Fuel can spray out if the fill nozzle is
inserted too quickly. This spray can
happen if the tank is nearly full, and is
more likely in hot weather. Insert the
fill nozzle slowly and wait for any hiss
noise to stop before beginning to
flow fuel.
To open the fuel door, push and release the
rearward center edge of the door.The capless refueling system does not have
a fuel cap. Fully insert and latch the fill
nozzle, then begin fueling.
{Warning
Overfilling the fuel tank by more than
three clicks of a standard fill nozzle may
cause:
.Vehicle performance issues, including
engine stalling and damage to the fuel
system.
.Fuel spills.
.Under certain conditions, fuel fires.
Be careful not to spill fuel. Wait five seconds
after you have finished pumping before
removing the fill nozzle. Clean fuel from
painted surfaces as soon as possible. See
Exterior Care 0337. Push the fuel door
closed until it latches.
{Warning
If a fire starts while you are refueling, do
not remove the fill nozzle. Shut off the
flow of fuel by shutting off the pump or
by notifying the station attendant. Leave
the area immediately. Filling the Tank with a Portable Fuel
Container
If the vehicle runs out of fuel and must be
filled from a portable fuel container:
1. Locate the capless funnel adapter from
the rear cargo area under the load floor.
2. Insert and latch the funnel into the capless fuel system.
{Warning
Attempting to refuel from a portable fuel
container without using the funnel
adapter may cause fuel spillage and
damage the capless fuel system. This
could cause a fire. You or others could be
badly burned and the vehicle could be
damaged.
3. Remove and clean the funnel adapter and return it to the storage location.

GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-14608671) - 2021 - CRC - 10/26/20
Driving and Operating 257
When towing a trailer:
.Become familiar with and follow all state
and local laws that apply to trailer
towing. These requirements vary from
state to state.
.State laws may require the use of
extended side view mirrors. Even if not
required, you should install extended side
view mirrors if your visibility is limited or
restricted while towing.
.Do not tow a trailer during the first
800 km (500 mi) of vehicle use to prevent
damage to the engine, axle, or other
parts.
.It is recommended to perform the first oil
change before heavy towing.
.During the first 800 km (500 mi) of trailer
towing, do not drive over 80 km/h
(50 mph) and do not make starts at full
throttle.
.Vehicles can tow in D (Drive). Tow/Haul
Mode is recommended for heavier trailers.
SeeTow/Haul Mode 0224. If the
transmission downshifts too often, a
lower gear may be selected using Manual
Mode. See Manual Mode 0223. If equipped, the following driver assistance
features should be turned off when towing
a trailer:
.Adaptive Cruise Control (ACC)
.Super Cruise Control
.Lane Keep Assist (LKA)
.Park Assist
.Automatic Parking Assist (APA)
.Reverse Automatic Braking (RAB)
If equipped, the following driver assistance
features should be turned to alert or off
when towing a trailer:
.Automatic Emergency Braking (AEB)
.Intelligent Brake Assist (IBA)
.Front Pedestrian Braking (FPB)
If equipped with Lane Change Alert (LCA),
the LCA detection zones that extend back
from the side of the vehicle do not move
further back when a trailer is towed. Use
caution while changing lanes when towing a
trailer.
If equipped with Rear Cross Traffic Alert
(RCTA), use caution while backing up when
towing a trailer, as the RCTA detection zones
that extend out from the back of the vehicle
do not move further back when a trailer is
towed.
{Warning
To prevent serious injury or death from
carbon monoxide (CO), when towing a
trailer:
.Do not drive with the liftgate, trunk/
hatch, or rear-most window open.
.Fully open the air outlets on or under
the instrument panel.
.Adjust the climate control system to a
setting that brings in only outside air.
See “Climate Control Systems” in the
Index.
For more information about carbon
monoxide, see Engine Exhaust 0219.
Towing a trailer requires experience. The
combination of the vehicle and trailer is
longer and not as responsive as the vehicle
itself. Get used to the handling and braking
of the combination by driving on a level
road surface before driving on public roads.
The trailer structure, the tires, and the
brakes must be all be rated to carry the
intended cargo. Inadequate trailer
equipment can cause the combination to
operate in an unexpected or unsafe manner.

GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-14608671) - 2021 - CRC - 10/26/20
258 Driving and Operating
Before driving, inspect all trailer hitch parts
and attachments, safety chains, electrical
connectors, lamps, tires, and mirrors. See
Towing Equipment0262. If the trailer has
electric brakes, start the combination
moving and then manually apply the trailer
brake controller to check the trailer brakes
work. During the trip, occasionally check
that the cargo and trailer are secure and
that the lamps and any trailer brakes are
working.
Towing with a Stability Control System
When towing, the stability control system
might be heard. The system reacts to
vehicle movement caused by the trailer,
which mainly occurs during cornering. This is
normal when towing heavier trailers.
Following Distance
Stay at least twice as far behind the vehicle
ahead as you would when driving without a
trailer. This can help to avoid heavy braking
and sudden turns.
Passing
More passing distance is needed when
towing a trailer. The combination of the
vehicle and trailer will not accelerate as
quickly and is much longer than the vehicle
alone. It is necessary to go much farther
beyond the passed vehicle before returning
to the lane. Pass on level roadways. Avoid
passing on hills if possible.
Backing Up
Hold the bottom of the steering wheel with
one hand. To move the trailer to the left,
move that hand to the left. To move the
trailer to the right, move that hand to the
right. Always back up slowly and, if possible,
have someone guide you.
Making Turns
Caution
Turn more slowly and make wider arcs
when towing a trailer to prevent damage
to your vehicle. Making very sharp turns
could cause the trailer to contact the
vehicle. Make wider turns than normal when towing,
so the trailer will not go over soft shoulders,
over curbs, or strike road signs, trees,
or other objects. Always signal turns well in
advance. Do not steer or brake suddenly.
Driving on Grades
Reduce speed and shift to a lower gear
before starting down a long or steep
downhill grade. If the transmission is not
shifted down, the brakes may overheat and
result in reduced braking efficiency.
The vehicle can tow in D (Drive). Shift the
transmission to a lower gear if the
transmission shifts too often under heavy
loads and/or hilly conditions.
When towing at higher altitudes, engine
coolant will boil at a lower temperature
than at lower altitudes. If the engine is
turned off immediately after towing at high
altitude on steep uphill grades, the vehicle
could show signs similar to engine
overheating. To avoid this, let the engine
run, preferably on level ground, with the
transmission in P (Park) for a few minutes
before turning the engine off. If the
overheat warning comes on, see
Engine
Overheating 0285.