2021 GMC ACADIA trailer

GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-14608671) - 2021 - CRC - 10/26/20
Driving and Operating 259
Viewing Systems
If equipped, the viewing systems on the
vehicle can improve visibility while hitching,
backing, and driving with a trailer. See
Driver Assistance Systems0239 and
Assistance Systems for Parking or Backing
0 241.
Parking on Hills
{Warning
To prevent serious injury or death,
always park your vehicle and trailer on a
level surface when possible.
When parking your vehicle and your trailer
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, gradually release the brake pedal to
allow the chocks to absorb the load of
the trailer. 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:
.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
used to tow trailers. See Maintenance
Schedule 0346. It is especially important to
check the engine oil, axle lubricant, belts,
cooling system, and brake system before
and during each trip.
Check periodically that all nuts and bolts on
the trailer hitch are tight.
Engine Cooling When Trailer Towing
The cooling system may temporarily
overheat during severe operating conditions.
See Engine Overheating 0285.
Trailer Towing
Caution
Towing a trailer improperly can damage
the vehicle and result in costly repairs
not covered by the vehicle warranty. To
tow a trailer correctly, follow the
directions in this section and see your
dealer for important information about
towing a trailer with the vehicle.
Trailer Weight
{Warning
Never exceed the towing capacity for
your vehicle.
Safe trailering requires monitoring the
weight, speed, altitude, road grades, outside
temperature, dimensions of the front of the
trailer, and how frequently the vehicle is
used to tow a trailer.

GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-14608671) - 2021 - CRC - 10/26/20
260 Driving and Operating
Trailer Weight Ratings
When towing a trailer, the weight of the
loaded vehicle and trailer must be within
the weight ratings for the vehicle.
.GCWR: Gross Combined Weight Rating
.GVWR: Gross Vehicle Weight Rating
.Maximum Trailer Weight Rating
.Maximum Trailer Tongue Weight
The only way to be sure the weight is not
exceeding any of these ratings is to weigh
the tow vehicle and trailer combination,
fully loaded for the trip, getting individual
weights for each of these items.
{Warning
You and others could be seriously injured
or killed if the trailer is too heavy or the
trailer brakes are inadequate for the load.
The vehicle may be damaged, and the
repairs would not be covered by the
vehicle warranty.
Only tow a trailer if all the steps in this
section have been followed. Ask your
dealer for advice and information about
towing a trailer.
Gross Combined Weight Rating (GCWR)
GCWR is the total allowable weight of the
completely loaded vehicle and trailer
including any fuel, passengers, cargo,
equipment, and accessories. Do not exceed
the GCWR for your vehicle. The GCWR for
the vehicle is on the Tow Rating Chart
following.
Gross Vehicle Weight Rating (GVWR)
For information about the vehicle's
maximum load capacity, see Vehicle Load
Limits 0209. When calculating the GVWR
with a trailer attached, the trailer tongue
weight must be included as part of the
weight the vehicle is carrying.
Maximum Trailer Weight Rating
The maximum trailer weight rating is
calculated assuming the tow vehicle has a
driver, a front seat passenger, and all
required trailering equipment. Weight of
additional optional equipment, passengers,
and cargo in the tow vehicle must be
subtracted from the trailer weight rating.
Use the tow rating chart to determine how
much the trailer can weigh, based on the
vehicle model, powertrain and trailering
options.

GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-14608671) - 2021 - CRC - 10/26/20
Driving and Operating 261
VehicleMaximum Trailer Weight *GCWR
2.0L LSY Engine 680 kg (1,500 lb)2 835 kg (6,250 lb)
2.5L LCV Engine 454 kg (1,000 lb)2 722 kg (6,000 lb)
3.6L LGX Engine, With V92 Trailer Towing Package 1 814 kg (4,000 lb)4 075 kg (8,984 lb)
3.6L LGX Engine, Without V92 Trailer Towing Package 454 kg (1,000 lb)2 722 kg (6,000 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.
Maximum Trailer Tongue Weight Rating
The Maximum Trailer Tongue Weight Rating
is the allowable trailer tongue weight that
the vehicle can support. Do not exceed a
maximum trailer tongue weight of 400 lbs.
The trailer tongue weight contributes to the
Gross Vehicle Weight (GVW). GVW includes
the CURB WEIGHT of your vehicle, any
passengers, cargo, equipment and the trailer
tongue weight. Vehicle options, passengers,
cargo, and equipment reduce the maximum
allowable tongue weight the vehicle can
carry, which also reduces the maximum
allowable trailer weight.
Trailer Load Balance
The correct trailer load balance must be
maintained to ensure trailer stability.
Incorrect load balance is a leading cause of
trailer sway.
The trailer tongue weight (1) should be
10–15% of the loaded trailer weight (2).
Some specific trailer types, such as boat
trailers, fall outside of this range. Always
refer to the trailer owner’s manual for the

GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-14608671) - 2021 - CRC - 10/26/20
262 Driving and Operating
recommended trailer tongue weight for each
trailer. Never exceed the maximum loads for
your vehicle, hitch and trailer.
After loading the trailer, separately weigh
the trailer and then the tongue to see if the
weights are proper. If the trailer tongue
weight is too high or too low, adjustments
might be made by moving some items
around in the trailer.
If a cargo carrier is used in the trailer hitch
receiver, choose a carrier that positions the
load as close to the vehicle as possible.
Make sure the total weight, including the
carrier, is no more than half of the
maximum allowable tongue weight for the
vehicle or 181 kg (400 lb), whichever is less.
Ask your dealer for trailering information or
assistance.
Towing Equipment
Hitches
Always use the correct hitch equipment for
your vehicle. Crosswinds, large trucks going
by, and rough roads can affect the trailer
and the hitch.Proper hitch equipment for your vehicle
helps maintain combination control. Many
trailers can be towed using a
weight-carrying hitch which has a coupler
latched to the hitch ball, or a tow eye
latched to a pintle hook. Other trailers may
require a weight-distributing hitch that uses
spring bars to distribute the trailer tongue
weight between your vehicle and trailer
axles. See
“Trailer Tongue Weight” under
Trailer Towing 0259 or weight limits with
various hitch types.
Never attach rental hitches or other
bumper-type hitches. Only use
frame-mounted hitches that do not attach to
the bumper.
Always seal any holes in your vehicle if the
trailer hitch removed. If not sealed, dirt,
water, and carbon monoxide (CO) from the
exhaust may enter your vehicle. See Engine
Exhaust 0219.
Hitch Cover
1. Upper Attachments
2. Fasteners
To remove hitch cover, if equipped:
1. Remove the two fasteners on the lower tabs (2).
2. Pull the lower edge of the cover to about a 45 degree angle.
3. Pull the cover downward to disengage the upper attachments (1).
To reinstall hitch cover: 1. Hold cover at a 45 degree angle to the vehicle and push the upper tabs into the
slots in the bumper.

GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-14608671) - 2021 - CRC - 10/26/20
Driving and Operating 263
2. Push the bottom of the cover forwarduntil the lower tabs line up with the
lower slots (1).
3. Snap the hitch cover into place by pushing the upper corners forward.
4. Reinstall the two fasteners on the lower tabs (2).
Consider using mechanical sway controls
with any trailer. Ask a trailering professional
about sway controls or refer to the trailer
manufacturer's recommendations and
instructions.
Weight-Distributing Hitch Adjustment
1. Front of Vehicle
2. Body to Ground Distance
When using a weight-distributing hitch,
measure the front fender height distance (2)
before connecting the trailer. Adjust the
spring bars until the front fender height
distance (2) is the same height before the
trailer was connected. Do not reduce the
front fender height below the initial
distance (2).
Tires
.Do not tow a trailer while using a
compact spare tire on the vehicle.
.Tires must be properly inflated to support
loads while towing a trailer. See Tires
0 300 for instructions on proper tire
inflation.
Safety Chains
Always attach chains between the vehicle
and the trailer, and attach the chains to the
holes on the trailer hitch platform.
Instructions about safety chains may be
provided by the hitch manufacturer or by
the trailer manufacturer.
Cross the safety chains under the tongue of
the trailer to help prevent the tongue from
contacting the road if it becomes separated
from the hitch. Always leave just enough
slack so the combination can turn. Never
allow safety chains to drag on the ground.
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.

GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-14608671) - 2021 - CRC - 10/26/20
264 Driving and Operating
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:
Electric Trailer
Brakes Blue
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.

GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-14608671) - 2021 - CRC - 10/26/20
Driving and Operating 265
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, seeDriver Mode Control 0228.
Tow/Haul assists when pulling a heavy
trailer or a large or heavy load. See Tow/
Haul Mode 0224.
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 0259.
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
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. See
Traction Control/Electronic Stability Control
0
226.
{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 0262 for trailer
ratings and hitch setup recommendations.

GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-14608671) - 2021 - CRC - 10/26/20
266 Driving and Operating
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.
Overloading is another leading cause of
trailer tire blow-outs. Never load your trailer
with more weight than the tires are
designed to support. The load rating is
located on the trailer tire sidewall.
Always know the maximum speed rating for
the trailer tires before driving. This may be
significantly lower than the vehicle tire
speed rating. The speed rating may be onthe trailer tire sidewall. If the speed rating is
not shown, the default trailer tire speed
rating is 105 km/h (65 mph).
Conversions and Add-Ons
Add-On Electrical Equipment
{Warning
The Data Link Connector (DLC) is used for
vehicle service and Emission Inspection/
Maintenance testing. See
Malfunction
Indicator Lamp (Check Engine Light) 0107
. A device connected to the DLC —such
as an aftermarket fleet or driver-behavior
tracking device —may interfere with
vehicle systems. This could affect vehicle
operation and cause a crash. Such devices
may also access information stored in the
vehicle’s systems.
Caution
Some electrical equipment can damage
the vehicle or cause components to not
work and would not be covered by the
vehicle warranty. Always check with your
dealer before adding electrical equipment.
Add-on equipment can drain the vehicle's
12-volt battery, even if the vehicle is not
operating.
The vehicle has an airbag system. Before
attempting to add anything electrical to the
vehicle, see Servicing the Airbag-Equipped
Vehicle 063 and
Adding Equipment to the Airbag-Equipped
Vehicle 063.