
GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13687875) - 2020 - CRC - 10/28/19
Driving and Operating 255
Trailer Brakes
Loaded trailers over 450 kg
(1,000 lb) must be equipped with
brake systems and with brakes for
each axle. Trailer braking equipment
conforming to Canadian Standards
Association (CSA) requirement
CAN3-D313, or its equivalent, is
recommended.
State or local regulations may
require trailers to have their own
braking system if the loaded weight
of the trailer exceeds certain
minimums that can vary from state
to state. Read and follow the
instructions for the trailer brakes so
they are installed, adjusted, and
maintained properly. Never attempt
to tap into your vehicle's hydraulic
brake system. If you do, both the
vehicle anti-lock brakes and the
trailer brakes may not function,
which could result in a crash.
Trailer Wiring Harness
lf equipped, the trailer wiring
harness, with a 7-pin connector is
mounted on the trailer hitch.
1. Left Turn/Brake
2. Tail Lamps
3. Reverse Lamps
4. Battery feed
5. Right Turn/Brake
6. Electric Brakes
7. Ground
If the vehicle is not equipped with a
trailer connector on the trailer hitch,
a 7-wire trailering harness is tied to
the vehicles frame. The harness
requires the installation of a trailer
connector, which is available
through your dealer.Use only a round, seven-wire
connector with flat blade terminals
meeting SAE J2863 specifications
for proper electrical connectivity.
The seven-wire harness contains
the following trailer circuits:
Stop/Turn
Signal Left Yellow/Gray
Stop/Turn
Signal Right Green/Violet
Tail/Parking
Lamps Gray/Brown
Reverse Lamps White/Green
Battery Feed Red/Green
Ground Black
Electric Trailer
Brake Blue
Electric Brake Control Wiring
Provisions
If equipped, (4) blunt-cut wires are
located near the driver's feet for an
aftermarket electric trailer brake
controller as part of the trailer wiring
package. The harness contains the
following circuits:

GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13687875) - 2020 - CRC - 10/28/19
256 Driving and Operating
Electric Trailer
BrakesBlue
Battery Feed Red/Black or
Red/Blue
Brake Apply
Signal White/Blue
Ground Black
Refer to the aftermarket electric
trailer brake controller owner's
manual to determine wire color
coding of the electric trailer brake
controller. The wire colors on the
brake controller may be different
from the vehicle. It may be
necessary to have a technician
connect the 12-volt power to the
engine compartment fuse block. The
electric trailer brake controller
should be installed by your dealer or
a qualified service center.
Trailer Lamps
Always check all trailer lamps are
working at the beginning of each
trip, and periodically on longer trips.
Turn Signals When Towing a
Trailer
When properly connected, the trailer
turn signals should will illuminate to
indicate the vehicle is turning,
changing lanes, or stopping. When
towing a trailer, the arrows on the
instrument cluster will illuminate
even if the trailer is not properly
connected or the bulbs are
burned out.
Tow/Haul Mode
For instructions on how to enter
Tow/Haul mode, see Driver Mode
Control 0212.
Tow/Haul assists when pulling a
heavy trailer or a large or heavy
load. See Tow/Haul Mode 0206.
Tow/Haul Mode is designed to be
most effective when the vehicle and
trailer combined weight is at least
75% of the vehicle's Gross
Combined Weight Rating (GCWR).
See “Weight of the Trailer” under
Trailer Towing 0250. Tow/Haul Mode is most useful when
towing a heavy trailer or carrying a
large or heavy load:
.
through rolling terrain
. in stop-and-go traffic
. in busy parking lots
Operating the vehicle in Tow/Haul
Mode when lightly loaded or not
towing will not cause damage;
however, it is not recommended and
may result in unpleasant engine and
transmission driving characteristics
and reduced fuel economy.
Trailer Sway
Control (TSC)
Vehicles with StabiliTrak/Electronic
Stability Control (ESC) have a
Trailer Sway Control (TSC) feature.
Trailer sway is unintended
side-to-side motion of a trailer while
towing. If the vehicle is towing a
trailer and the TSC detects that
sway is increasing, the vehicle
brakes are selectively applied at
each wheel, to help reduce
excessive trailer sway. If equipped
with the Integrated Trailer Brake

GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13687875) - 2020 - CRC - 10/28/19
Driving and Operating 257
Control (ITBC) system, and the
trailer has an electric brake system,
StabiliTrak/ESC may also apply the
trailer brakes.
If TSC is enabled, the Traction
Control System (TCS)/StabiliTrak/
ESC warning light will flash on the
instrument cluster. Reduce vehicle
speed by gradually removing your
foot from the accelerator. If trailer
sway continues, StabiliTrak/ESC
can reduce engine torque to help
slow the vehicle. TSC will not
function if StabiliTrak/ESC is turned
off. SeeTraction Control/Electronic
Stability Control 0209.
{Warning
Trailer sway can result in a crash
and in serious injury or death,
even if the vehicle is equipped
with TSC.
If the trailer begins to sway,
reduce vehicle speed by
gradually removing your foot from
the accelerator. Then pull over to
check the trailer and vehicle to
help correct possible causes,
including an improperly or
overloaded trailer, unrestrained
cargo, improper trailer hitch
configuration, or improperly
inflated or incorrect vehicle or
trailer tires. See Towing
Equipment 0253 for trailer ratings
and hitch setup
recommendations.
Trailer Tires
Special Trailer (ST) tires differ from
vehicle tires. Trailer tires are
designed with stiff sidewalls to help
prevent sway and to support heavy
loads. These features can make it
difficult to determine if the trailer tire
pressures are low only based on a
visual inspection.
Always check all trailer tire
pressures before each trip when the
tires are cool. Low trailer tire
pressure is a leading cause of trailer
tire blow-outs.
Trailer tires deteriorate over time.
The trailer tire sidewall will show the
week and year the tire was
manufactured. Many trailer tire
manufacturers recommend
replacing tires more than six
years old.

GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13687875) - 2020 - CRC - 10/28/19
Vehicle Care 259
Vehicle Care
General Information
General Information . . . . . . . . . . 260
California Proposition65 Warning . . . . . . . . . . . . . . . . . 260
California Perchlorate Materials Requirements . . . . . 261
Accessories and Modifications . . . . . . . . . . . . . . . . 261
Vehicle Checks
Doing Your OwnService Work . . . . . . . . . . . . . . . 261
Hood . . . . . . . . . . . . . . . . . . . . . . . . . 262
Engine Compartment Overview . . . . . . . . . . . . . . . . . . . . 264
Engine Oil . . . . . . . . . . . . . . . . . . . . 269
Engine Oil Life System . . . . . . . 271
Automatic Transmission Fluid . . . . . . . . . . . . . . . . . . . . . . . . 272
Engine Air Filter Life System . . . . . . . . . . . . . . . . . . . . . . 273
Engine Air Cleaner/Filter . . . . . . 273
Cooling System . . . . . . . . . . . . . . 275
Engine Overheating . . . . . . . . . . 279
Washer Fluid . . . . . . . . . . . . . . . . . 281
Brakes . . . . . . . . . . . . . . . . . . . . . . . 281
Brake Fluid . . . . . . . . . . . . . . . . . . . 282 Battery - North America . . . . . . 283
All-Wheel Drive . . . . . . . . . . . . . . . 284
Starter Switch Check . . . . . . . . . 284
Park Brake and P (Park)
Mechanism Check . . . . . . . . . . 285
Wiper Blade Replacement . . . . 285
Windshield Replacement . . . . . 286
Gas Strut(s) . . . . . . . . . . . . . . . . . . 286
Headlamp Aiming
Front Headlamp Aiming . . . . . . 288
Bulb Replacement
Bulb Replacement . . . . . . . . . . . . 288
Halogen Bulbs . . . . . . . . . . . . . . . . 288
LED Lighting . . . . . . . . . . . . . . . . . 288
Electrical System
Electrical System Overload . . . 289
Fuses and Circuit Breakers . . . 289
Engine Compartment Fuse Block . . . . . . . . . . . . . . . . . . . . . . . . 290
Instrument Panel Fuse Block . . . . . . . . . . . . . . . . . . . . . . . . 293
Rear Compartment Fuse Block . . . . . . . . . . . . . . . . . . . . . . . . 295
Wheels and Tires
Tires . . . . . . . . . . . . . . . . . . . . . . . . . . 297
All-Season Tires . . . . . . . . . . . . . . 298
Winter Tires . . . . . . . . . . . . . . . . . . 299
Summer Tires . . . . . . . . . . . . . . . . 299 Tire Sidewall Labeling . . . . . . . . 300
Tire Designations . . . . . . . . . . . . . 302
Tire Terminology and
Definitions . . . . . . . . . . . . . . . . . . 302
Tire Pressure . . . . . . . . . . . . . . . . . 305
Tire Pressure for High-Speed
Operation . . . . . . . . . . . . . . . . . . . 306
Tire Pressure Monitor System . . . . . . . . . . . . . . . . . . . . . . 307
Tire Pressure Monitor Operation . . . . . . . . . . . . . . . . . . . 308
Tire Inspection . . . . . . . . . . . . . . . . 312
Tire Rotation . . . . . . . . . . . . . . . . . 312
When It Is Time for New Tires . . . . . . . . . . . . . . . . . . . . . . . . 313
Buying New Tires . . . . . . . . . . . . . 314
Different Size Tires and Wheels . . . . . . . . . . . . . . . . . . . . . . 315
Uniform Tire Quality Grading . . . . . . . . . . . . . . . . . . . . . 316
Wheel Alignment and Tire Balance . . . . . . . . . . . . . . . . . . . . . 317
Wheel Replacement . . . . . . . . . . 318
Tire Chains . . . . . . . . . . . . . . . . . . . 318
If a Tire Goes Flat . . . . . . . . . . . . 319
Tire Sealant and Compressor Kit . . . . . . . . . . . . . 321
Storing the Tire Sealant and Compressor Kit . . . . . . . . . . . . . 327
Tire Changing . . . . . . . . . . . . . . . . 328

GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13687875) - 2020 - CRC - 10/28/19
Vehicle Care 261
California Perchlorate
Materials Requirements
Certain types of automotive
applications, such as airbag
initiators, seat belt pretensioners,
and lithium batteries contained in
electronic keys, may contain
perchlorate materials. Perchlorate
Material–special handling may
apply. See www.dtsc.ca.gov/
hazardouswaste/perchlorate.
Accessories and
Modifications
Adding non-dealer accessories or
making modifications to the vehicle
can affect vehicle performance and
safety, including such things as
airbags, braking, stability, ride and
handling, emissions systems,
aerodynamics, durability, and
electronic systems like antilock
brakes, traction control, and stability
control. These accessories or
modifications could even cause
malfunction or damage not covered
by the vehicle warranty. Damage to suspension components
caused by modifying vehicle height
outside of factory settings will not be
covered by the vehicle warranty.
Damage to vehicle components
resulting from modifications or the
installation or use of non-GM
certified parts, including control
module or software modifications, is
not covered under the terms of the
vehicle warranty and may affect
remaining warranty coverage for
affected parts.
GM Accessories are designed to
complement and function with other
systems on the vehicle. See your
dealer to accessorize the vehicle
using genuine GM Accessories
installed by a dealer technician.
Also, see
Adding Equipment to the
Airbag-Equipped Vehicle 076.
Vehicle Checks
Doing Your Own
Service Work
{Warning
It can be dangerous to work on
your vehicle if you do not have
the proper knowledge, service
manual, tools, or parts. Always
follow owner ’s manual procedures
and consult the service manual
for your vehicle before doing any
service work.
If doing some of your own service
work, use the proper service
manual. It tells you much more
about how to service the vehicle
than this manual can. To order the
proper service manual, see
Publication Ordering Information
0 379.

GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13687875) - 2020 - CRC - 10/28/19
Vehicle Care 265
1.Engine Air Cleaner/Filter 0273.
2. Engine Oil Fill Cap. See Engine Oil 0269.
3. Engine Oil Dipstick. See Engine Oil 0269.
4. Engine Cooling Fan (Out of View). See Cooling System
0 275.
5. Brake Fluid Reservoir. See Brake Fluid 0282. 6.
Battery - North America 0283.
7. Engine Coolant Surge Tank and Pressure Cap. See
Cooling System 0275.
8. Positive (+) Battery Terminal (Under Cover). See Jump
Starting - North America 0335. 9. Windshield Washer Fluid
Reservoir. See Washer Fluid
0 281.
10. Engine Compartment Fuse
Block 0290.
11. Remote Negative (-) Battery Terminal. See Jump Starting -
North America 0335.

GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13687875) - 2020 - CRC - 10/28/19
Vehicle Care 267
1.Engine Air Cleaner/Filter 0273.
2. Engine Oil Fill Cap. See Engine Oil 0269.
3. Engine Oil Dipstick. See Engine Oil 0269.
4. Engine Cooling Fan (Out of View). See Cooling System
0 275. 5. Windshield Washer Fluid
Reservoir. See Washer Fluid
0 281.
6. Brake Fluid Reservoir. See Brake Fluid 0282.
7. Battery - North America 0283.
8. Engine Coolant Surge Tank and Pressure Cap. See
Cooling System 0275. 9. Positive (+) Battery Terminal
(Under Cover). See Jump
Starting - North America 0335.
10. Engine Compartment Fuse
Block 0290.
11. Remote Negative (-) Battery Terminal. See Jump Starting -
North America 0335.

GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13687875) - 2020 - CRC - 10/28/19
Vehicle Care 269
1.Engine Air Cleaner/Filter 0273.
2. Engine Oil Fill Cap. See Engine Oil 0269.
3. Engine Oil Dipstick. See Engine Oil 0269.
4. Engine Cooling Fan (Out of View). See Cooling System
0 275.
5. Windshield Washer Fluid Reservoir. See Washer Fluid
0 281.
6. Brake Fluid Reservoir. See Brake Fluid 0282.
7. Battery - North America 0283.
8. Engine Coolant Surge Tank and Pressure Cap. See
Cooling System 0275.
9. Positive (+) Battery Terminal. See Jump Starting - North
America 0335.
10. Engine Compartment Fuse
Block 0290.
11. Remote Negative (-) Battery Terminal. See Jump Starting -
North America 0335.Engine Oil
To ensure proper engine
performance and long life, careful
attention must be paid to engine oil.
Following these simple, but
important steps will help protect
your investment:
.
Use engine oil approved to the
proper specification and of the
proper viscosity grade. See
“Selecting the Right Engine Oil”
in this section.
. Check the engine oil level
regularly and maintain the
proper oil level. See “Checking
Engine Oil” and“When to Add
Engine Oil” in this section.
. Change the engine oil at the
appropriate time. See Engine Oil
Life System 0271.
. Always dispose of engine oil
properly. See “What to Do with
Used Oil” in this section.
Checking Engine Oil
Check the engine oil level regularly,
every 650 km (400 mi), especially
prior to a long trip. The engine oil dipstick handle is a loop. See
Engine Compartment Overview
0
264 for the location.
{Warning
The engine oil dipstick handle
may be hot; it could burn you.
Use a towel or glove to touch the
dipstick handle.
If a low oil Driver Information Center
(DIC) message displays, check the
oil level.
Follow these guidelines:
. To get an accurate reading, park
the vehicle on level ground.
Check the engine oil level after
the engine has been off for at
least two hours. Checking the
engine oil level on steep grades
or too soon after engine shutoff
can result in incorrect readings.
Accuracy improves when
checking a cold engine prior to
starting. Remove the dipstick
and check the level.