engine GMC ACADIA 2018 Repair Manual

GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349114) - 2018 - crc - 9/21/17
Driving and Operating 239
Driver Mode Control Knob
5orqTour (FWD) :Vehicle is
in Tour (FWD) Mode. Use this mode
during normal driving conditions.
See Driving for Better Fuel
Economy 027. 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.
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
0 350.6Snow/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
0 270.
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.

GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349114) - 2018 - crc - 9/21/17
242 Driving and Operating
.To decrease the vehicle speed in
small increments, briefly press
SET−. For each press, the
vehicle goes about 1 km/h
(1 mph) slower.
The speedometer reading can be
displayed in either English or metric
units. See Instrument Cluster 0127.
The increment value used depends
on the units displayed.
Passing Another Vehicle While
Using Cruise Control
Use the accelerator pedal to
increase the vehicle speed. When
you take your foot off the pedal, the
vehicle will slow down to the
previous set cruise speed.
While pressing the accelerator pedal
or shortly following the release to
override cruise, briefly applying
SET− will result in cruise set to the
current vehicle speed.
Using Cruise Control on Hills
How well the cruise control will work
on hills depends upon the vehicle
speed, load, and the steepness of
the hills. When going up steep hills, you might have to step on the
accelerator pedal to maintain your
speed. While on a hill, the
transmission may downshift in order
to use engine braking to slow the
vehicle and maintain the set speed.
Also, you may have to brake or shift
to a lower gear to keep your speed
down. If the brake pedal is applied,
cruise control disengages.
Ending Cruise Control
There are four ways to end cruise
control:
.
Step lightly on the brake pedal.
. Press
*.
. Shift the transmission to
N (Neutral).
. Press
J.
Erasing Speed Memory
The cruise control set speed is
erased from memory if
Jis
pressed or if the ignition is
turned off.
Adaptive Cruise Control
If equipped with Adaptive Cruise
Control (ACC), it allows the driver to
select the cruise control set speed
and following gap. Read this entire
section before using this system.
The following gap is the following
time between your vehicle and a
vehicle detected directly ahead in
your path, moving in the same
direction. If no vehicle is detected in
your path, ACC works like regular
cruise control. ACC uses camera
and radar sensors. See Radio
Frequency Statement 0394.
If a vehicle is detected in your path,
ACC can apply acceleration or
limited, moderate braking to
maintain the selected following gap.
To disengage ACC, apply the brake.
If ACC is controlling your vehicle
speed when the Traction Control
System (TCS) or StabiliTrak
®
electronic stability control system
activates, the ACC may
automatically disengage. See
Traction Control/Electronic Stability
Control 0236. When road

GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349114) - 2018 - crc - 9/21/17
Driving and Operating 267
Fuel
GM recommends the use of TOP
TIER detergent gasoline to keep the
engine cleaner and reduce engine
deposits. See www.toptiergas.com
for a list of TOP TIER detergent
gasoline marketers and applicable
countries.
Do not use any fuel labeled E85 or
FlexFuel. Do not use gasoline with
ethanol levels greater than 15% by
volume.
Use regular unleaded gasoline
meeting ASTM specification D4814
with a posted octane rating of 87 orhigher. Do not use gasoline with a
posted octane rating of less than 87,
as this may cause engine knock and
will lower fuel economy.
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 which 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, and
aniline. These fuels can
corrode metal fuel system
parts or damage plastic and
rubber parts.
(Continued)
Caution (Continued)
.Fuel containing metals such
as methylcyclopentadienyl
manganese tricarbonyl
(MMT), which can damage
the emissions control
system and spark plugs.
. 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.
California Fuel
Requirements
If the vehicle is certified to meet
California Emissions Standards, it is
designed to operate on fuels that
meet California specifications. See
the underhood emission control
label. If this fuel is not available in
states adopting California Emissions
Standards, the vehicle will operate
satisfactorily on fuels meeting

GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349114) - 2018 - crc - 9/21/17
268 Driving and Operating
federal specifications, but emission
control system performance may be
affected. The malfunction indicator
lamp could turn on and the vehicle
may not pass a smog-check test.
SeeMalfunction Indicator Lamp
(Check Engine Light) 0136. If this
occurs, return to your authorized
dealer for diagnosis. If it is
determined that the condition is
caused by the type of fuel used,
repairs may not be covered by the
vehicle warranty.
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
Fuels” inFuel 0267.
Fuel Additives
To keep fuel systems clean, TOP
TIER detergent gasoline is
recommended. See Fuel0267. If TOP TIER detergent gasoline is
not available, one bottle of GM Fuel
System Treatment Cleaner added to
the fuel tank at every engine oil
change, can help. GM Fuel System
Treatment Cleaner is the only
gasoline additive recommended by
General Motors. It is available at
your dealer.
Filling the Tank
{Warning
Fuel vapors and fuel fires burn
violently and can cause injury or
death.
. 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.
(Continued)
Warning (Continued)
.Do not leave the fuel pump
unattended.
. Do not use a cell phone
while refueling.
. Do not reenter the vehicle
while pumping fuel.
. Keep children away from
the fuel pump and never let
children pump fuel.
. Fuel can spray out if the
refueling nozzle is inserted
too quickly. This spray can
happen if the tank is nearly
full, and is more likely in hot
weather. Insert the refueling
nozzle slowly and wait for
any hiss noise to stop prior
to beginning to flow fuel.

GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349114) - 2018 - crc - 9/21/17
Driving and Operating 269
To open the fuel door, push and
release the rearward center edge of
the door.
The vehicle has a capless refueling
system and does not have a fuel
cap. The filling nozzle must be fully
inserted and latched prior to starting
fuel flow.
{Warning
Overfilling the fuel tank by more
than three clicks of a standard fill
nozzle may cause:(Continued)
Warning (Continued)
.Vehicle performance issues,
including engine stalling and
damage to the fuel system.
. Fuel spills.
. Potential fuel fires.
Be careful not to spill fuel. Wait a
few seconds after you have finished
pumping before removing the
nozzle. Clean fuel from painted
surfaces as soon as possible. See
Exterior Care 0358.
{Warning
If a fire starts while you are
refueling, do not remove the
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
Gas Can
If the vehicle runs out of fuel and
must be filled from a portable
gas can:
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 without using
the funnel adapter may cause fuel
spillage and damage the capless
fuel system. This could cause a
fire and you or others could be
badly burned and the vehicle
could be damaged.

GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349114) - 2018 - crc - 9/21/17
Driving and Operating 271
.Do not tow a trailer during the
first 800 km (500 mi), to prevent
damage to the engine, axle or
other parts.
. Then, during the first 800 km
(500 mi) trailer towing, do not
drive over 80 km/h (50 mph) and
do not make starts at full throttle.
. The vehicle can tow in D (Drive)
but Manual Mode is
recommended. See Manual
Mode 0231. Use a lower gear if
the transmission shifts too often.
. Turn off Parking Assist and Rear
Cross Traffic Alert (RCTA) when
towing.
. Turn off Lane Keep Assist (LKA)
when towing.
. Do not use Adaptive Cruise
Control (ACC) when towing a
trailer.{Warning
When towing a trailer, exhaust
gases may collect at the rear of
the vehicle and enter if the
liftgate, trunk/hatch, or rear-most
window is open.
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.
. Also adjust the climate
control system to a setting
that brings in only outside
air. See “Climate Control
Systems” in the Index.
For information about carbon
monoxide, see Engine Exhaust
0 228.
Towing a trailer requires a certain
amount of experience. The
combination you are driving is longer and not as responsive as the
vehicle itself. Get acquainted with
the handling and braking of the rig
before setting out for the open road.
Before starting, check all trailer hitch
parts and attachments, safety
chains, electrical connectors, lamps,
tires, and mirrors. If the trailer has
electric brakes, start the
combination moving and then apply
the trailer brake controller by hand
to be sure the brakes work.
During the trip, check occasionally
to be sure that the load is secure
and the lamps and any trailer
brakes still work.
Towing with a Stability Control
System
When towing, the sound of the
stability control system might be
heard. The system is reacting to the
vehicle movement caused by the
trailer, which mainly occurs during
cornering. This is normal when
towing heavier trailers.

GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349114) - 2018 - crc - 9/21/17
272 Driving and Operating
Following Distance
Stay at least twice as far behind the
vehicle ahead as you would when
driving the vehicle without a trailer.
This can help to avoid situations
that require heavy braking and
sudden turns.
Passing
More passing distance is needed
when towing a trailer. Because the
rig is longer, it is necessary to go
farther beyond the passed vehicle
before returning to the lane.
Backing Up
Hold the bottom of the steering
wheel with one hand. To move the
trailer to the left, move your hand to
the left. To move the trailer to the
right, move your hand to the right.
Always back up slowly and,
if possible, have someone
guide you.
Making TurnsCaution
Making very sharp turns while
trailering could cause the trailer to
come in contact with the vehicle.
The vehicle could be damaged.
Avoid making very sharp turns
while trailering.
When turning with a trailer, make
wider turns than normal so the
trailer will not strike soft shoulders,
curbs, road signs, trees, or other
objects. Use the turn signal well in
advance and avoid jerky or sudden
maneuvers.
Turn Signals When Towing a
Trailer
The turn signal indicators on the
instrument cluster flash whenever
signaling a turn or lane change.
Properly hooked up, the trailer
lamps also flash, telling other
drivers the vehicle is turning,
changing lanes, or stopping. When towing a trailer, the arrows on
the instrument cluster flash for turns
even if the bulbs on the trailer are
burned out. Check occasionally to
be sure the trailer bulbs are still
working.
Driving on Grades
Reduce speed and shift to a lower
gear before starting down a long or
steep downgrade. If the
transmission is not shifted down, the
brakes might have to be used so
much that they would get hot and no
longer work well.
The vehicle can tow in D (Drive).
Use a lower gear if the transmission
shifts too often.
The Tow/Haul Mode may be used if
the transmission shifts too often.
See
Tow/Haul Mode 0232.
When towing at high altitude on
steep uphill grades, engine coolant
boils at a lower temperature than at
normal 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.

GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349114) - 2018 - crc - 9/21/17
Driving and Operating 273
To avoid this, let the engine run
while parked, 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 Overheating0295.
Parking on Hills
{Warning
Parking the vehicle on a hill with
the trailer attached can be
dangerous. If something goes
wrong, the rig could start to move.
People can be injured, and both
the vehicle and the trailer can be
damaged. When possible, always
park the rig on a flat surface.
If parking the rig on a hill: 1. Press the brake pedal, but do not shift into P (Park) yet. Turn
the wheels into the curb if
facing downhill or into traffic if
facing uphill.
2. Have someone place chocks under the trailer wheels. 3. When the wheel chocks are in
place, release the brake pedal
until the chocks absorb
the load.
4. Reapply the brake pedal. Then apply the parking brake and
shift into P (Park).
5. Release the brake pedal.
Leaving After Parking on a Hill
1. Apply and hold the brake pedal while you:
.Start the engine.
. Shift into a gear.
. Release the parking brake.
2. Let up on the brake pedal.
3. Drive slowly until the trailer is clear of the chocks.
4. Stop and have someone pick up and store the chocks.
Maintenance When Trailer
Towing
The vehicle needs service more
often when pulling a trailer. See
Maintenance Schedule 0369. Things that are especially important
in trailer operation are automatic
transmission fluid, engine oil, axle
lubricant, belts, cooling system and
brake system. Inspect these before
and during the trip.
Check periodically to see that all
hitch nuts and bolts are tight.
Engine Cooling When Trailer
Towing
The cooling system may temporarily
overheat during severe operating
conditions. See
Engine Overheating
0 295.
Trailer Towing
Three important considerations
have to do with weight:
.
The weight of the trailer.
. The weight of the trailer tongue.
. The total weight on the vehicle's
tires.

GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349114) - 2018 - crc - 9/21/17
Driving and Operating 275
VehicleMaximum Trailer Weight *GCWR
2.5L and 3.6L Engines 454 kg (1,000 lb)2 722 kg (6,000 lb)
3.6L Engine With V92 Trailer Towing Package 1 814 kg (4,000 lb)4 075 kg (8,984 lb)
*The Gross Combination Weight Rating (GCWR) is the total allowable weight of the completely loaded vehicle and
trailer including any passengers, cargo, equipment, and conversions. The GCWR for the vehicle should not be
exceeded.
Ask your dealer for trailering
information or advice.
Weight of the Trailer Tongue
The tongue load (1) of any trailer is
an important weight to measure
because it affects the total gross
weight of the vehicle. The Gross
Vehicle Weight (GVW) includes the
curb weight of the vehicle, any
cargo carried in it, and the people
who will be riding in the vehicle.
If there are a lot of options,
equipment, passengers or cargo in
the vehicle, it will reduce the tongue
weight the vehicle can carry, which
will also reduce the trailer weight the
vehicle can tow. If towing a trailer,
the tongue load must be added to the GVW because the vehicle will
be carrying that weight, too. See
Vehicle Load Limits
0217.
In general, trailer tongue weight (1)
should be 10-15 percent of the
loaded trailer weight (2). Some specific trailer types (especially boat
trailers) fall outside of this range. In
this case, the recommended tongue
weight in the trailer owner
’s manual
should be observed. In all cases,
the maximum loads for the vehicle
series and hitch type should not be
exceeded.
After loading the trailer, weigh the
trailer and then the tongue,
separately, to see if the weights are
proper. If they are not, adjustments
might be made by moving some
items around in the trailer.
Trailering may be limited by the
vehicle's ability to carry tongue
weight. Tongue weight cannot cause
the vehicle to exceed the GVWR
(Gross Vehicle Weight Rating) or

GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349114) - 2018 - crc - 9/21/17
276 Driving and Operating
the RGAWR (Rear Gross Axle
Weight Rating). The effect of
additional weight may reduce the
trailering capacity more than the
total of the additional weight.
It is important that the vehicle does
not exceed any of its ratings—
GCWR, GVWR, RGAWR, Maximum
Trailer Rating or Tongue Weight.
The only way to be sure it is not
exceeding any of these ratings is to
weigh the vehicle and trailer.
Total Weight on the Vehicle's
Tires
Inflate the vehicle's tires to the
upper limit for cold tires. These
numbers can be found on the
Certification label or see Vehicle
Load Limits 0217 for more
information. Do not go over the
GVW limit for the vehicle, or the
GAWR, including the weight of the
trailer tongue. If using a weight
distributing hitch, do not go over the
rear axle limit before applying the
weight distribution spring bars.
Towing Equipment
Hitches
It is important to have the correct
hitch equipment. Crosswinds, large
trucks going by, and rough roads
are a few reasons why the right
hitch is needed.
. The rear bumper on the vehicle
is not intended for hitches. Do
not attach rental hitches or other
bumper-type hitches to it. Use
only a frame-mounted hitch that
does not attach to the bumper.
. Will any holes be made in the
body of the vehicle when the
trailer hitch is installed? If so,
then be sure to seal the holes
when the hitch is removed. If the
holes are not sealed, dirt, water,
and deadly carbon monoxide
(CO) from the exhaust may get
into the vehicle. See Engine
Exhaust 0228. Weight-Distributing Hitches and
Weight Carrying Hitches
1. Front of Vehicle
2. Body-to-Ground Distance
When using a weight-distributing
hitch, the hitch must be adjusted so
that the distance (2) remains the
same both before and after coupling
the trailer to the tow vehicle.
Safety Chains
Always attach chains between the
vehicle and the trailer. Cross the
safety chains under the tongue of
the trailer to help prevent the tongue
from contacting the road if it