
GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-9803770) - 2017 - crc - 7/12/16
Driving and Operating 275
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 Overheating0297.
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 0368.
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 0297.

GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-9803770) - 2017 - crc - 7/12/16
Driving and Operating 279
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
becomes separated from the hitch.
Always leave just enough slack so
the rig can turn. Never allow safety
chains to drag on the ground.
Trailer Brakes
A loaded trailer that weighs more
than 450 kg (1,000 lb) needs to have
its own brake system that is
adequate for the weight of the
trailer. Be sure to read and follow
the instructions for the trailer brakes
so they are installed, adjusted, and
maintained properly.
Because the vehicle has antilock
brakes, do not try to tap into the
vehicle's hydraulic brake system.
If you do, both brake systems will
not work well, or at all.
Trailer Wiring Harness
Basic Trailer Wiring
The trailer wiring harness, with a
seven-pin connector, is located at
the rear of the vehicle and is tied to
the vehicle's frame. The harness
connector can be plugged into a
seven-pin universal heavy-duty
trailer connector 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:
.Yellow/Gray: Stop/Turn
Signal Left
. Green/Violet: Stop/Turn Signal
Right
. Gray/Brown: Parking Lamps
. White/Green: Back-up Lamps
. Red/Green: Back-up Lamps
. Black: Ground
. Blue: Electric Brake* *The fuse for this circuit is installed
in the underhood electrical center,
but the wires are not connected.
They should be connected by your
dealer or a qualified service center.
If the back-up lamp circuit is not
functional, contact your dealer.
If a remote (non-vehicle) battery is
being charged, turn the Tow/Haul
Mode knob on the center console.
This will boost the vehicle system
voltage and properly charge the
battery. If the trailer is too light for
Tow/Haul Mode, turn on the
headlamps (non-HID only) as a
second way to boost the vehicle
system and charge the battery.

GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-9803770) - 2017 - crc - 7/12/16
280 Driving and Operating
Electric Trailer Brake Control
Wiring Provisions
These wiring provisions for an
electric trailer brake controller are
included with the vehicle as part of
the trailer wiring package. The
instrument panel contains blunt cut
wires above the parking brake
assembly for the electric trailer
brake controller. The harness
contains the following wires:
.Blue: “To Trailer”
. Red/Black or Red/Blue:
Battery Feed
. White/Blue: Brake Apply Signal
. Black: Ground
The electric trailer brake controller
should be installed by your dealer or
a qualified service center.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)
0 132. 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 085 and Adding Equipment
to the Airbag-Equipped
Vehicle 086.

GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-9803770) - 2017 - crc - 7/12/16
284 Vehicle Care
Keep a record with all parts receipts
and list the mileage and the date of
any service work performed. See
Maintenance Records0380.
Caution
Even small amounts of
contamination can cause damage
to vehicle systems. Do not allow
contaminants to contact the fluids,
reservoir caps, or dipsticks.
Hood
To open the hood:
1. Pull the hood release handle
with this symbol on it. It is
under the instrument panel on
the driver side of the vehicle.
2. At the front of the vehicle, pullup on the center of the hood,
and push the secondary hood
release to the right.
3. After you have partially lifted the hood, gas struts will
automatically take over to lift
and hold the hood in the fully
open position. Before closing the hood, be sure all
filler caps are on properly.
Pull the hood down to close. Lower
the hood until the lifting pressure of
the strut is reduced. Then allow the
hood to fall and latch into place
under its own weight. Check to
make sure the hood is closed. If the
hood does not fully latch, gently
push the hood down at the front and
center of the hood until it is
completely latched.

GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-9803770) - 2017 - crc - 7/12/16
288 Vehicle Care
1.Engine Air Cleaner/Filter 0292.
2. Engine Oil Fill Cap. See Engine Oil 0288.
3. Engine Oil Dipstick. See Engine Oil 0288.
4. Engine Cooling Fan (Out of View). See Cooling
System 0293.
5. Windshield Washer Fluid Reservoir. See Washer
Fluid 0298.
6. Brake Fluid Reservoir. See Brake Fluid 0300.
7. Battery - North America 0301.
8. Engine Coolant Surge Tank and Pressure Cap. See
Cooling System 0293.
9. Positive (+) Battery Terminal. See Jump Starting - North
America 0351.
10. Engine Compartment Fuse
Block 0307.
11. Remote Negative (-) Battery Terminal. See Jump Starting -
North America 0351.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 0290.
. 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
285 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.

GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-9803770) - 2017 - crc - 7/12/16
Vehicle Care 291
Change the oil as soon as possible
within the next 1 000 km (600 mi).
It is possible that, if driving under
the best conditions, the oil life
system might indicate that an oil
change is not necessary for up to a
year. The engine oil and filter must
be changed at least once a year
and, at this time, the system must
be reset. Your dealer has trained
service people who will perform this
work and reset the system. It is also
important to check the oil regularly
over the course of an oil drain
interval and keep it at the proper
level.
If the system is ever reset
accidentally, the oil must be
changed at 5 000 km (3,000 mi)
since the last oil change.
Remember to reset the oil life
system whenever the oil is changed.How to Reset the Engine Oil
Life System
Reset the system whenever the
engine oil is changed so that the
system can calculate the next
engine oil change. To reset the
system:1. Display the REMAINING OIL LIFE on the DIC. See Driver
Information Center (DIC) (Base
and Midlevel) 0141 orDriver
Information Center (DIC)
(Uplevel) 0144.
2. Press and hold
Von the DIC
while the Oil Life display is
active. The oil life will change
to 100%.
If the CHANGE ENGINE OIL SOON
message comes back on when the
vehicle is started, the engine oil life
system has not been reset. Repeat
the procedure.
Automatic Transmission
Fluid
It is not necessary to check the
transmission fluid level.
A transmission fluid leak is the only
reason for fluid loss. If a leak
occurs, take the vehicle to the
dealer and have it repaired as soon
as possible.
Change the fluid at the intervals
listed in Maintenance Schedule
0 368, and be sure to use the
transmission fluid listed in
Recommended Fluids and
Lubricants 0377.
Caution
Use of the incorrect automatic
transmission fluid may damage
the vehicle, and the damage may
not be covered by the vehicle
warranty. Always use the
automatic transmission fluid listed
in Recommended Fluids and
Lubricants 0377.

GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-9803770) - 2017 - crc - 7/12/16
292 Vehicle Care
The transmission fluid will not reach
the end of the dipstick unless the
transmission is at operating
temperature. If you need to check
the transmission fluid level, please
take the vehicle to your dealer.
Engine Air Cleaner/Filter
The engine air cleaner/filter is in the
engine compartment on the
passenger side of the vehicle. See
Engine Compartment Overview
0285 for location.
When to Inspect the Engine Air
Cleaner/Filter
For intervals on changing and
inspecting the engine air cleaner/
filter, see Maintenance
Schedule 0368.
How to Inspect the Engine Air
Cleaner/Filter
Do not start the engine or have the
engine running with the engine air
cleaner/filter housing open. Before
removing the engine air cleaner/
filter, make sure that the engine air
cleaner/filter housing and nearby
components are free of dirt and debris. Remove the engine air
cleaner/filter. Lightly tap and shake
the engine air cleaner/filter (away
from the vehicle), to release loose
dust and dirt. Inspect the engine air
cleaner/filter for damage, and
replace if damaged. Do not clean
the engine air cleaner/filter or
components with water or
compressed air.
To inspect or replace the air cleaner/
filter:
2.5L L4 Engine
1. Remove the five screws and lift the cover out of the assembly.
2. Inspect or replace the engine air cleaner/filter. 3. Lower the cover and secure
with the five screws.
3.6L V6 Engine
1. Remove the five screws and lift the cover out of the assembly.
2. Inspect or replace the engine air cleaner/filter.
3. Lower the cover and secure with the five screws.
{Warning
Operating the engine with the air
cleaner/filter off can cause you or
others to be burned. The air
(Continued)

GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-9803770) - 2017 - crc - 7/12/16
Vehicle Care 293
Warning (Continued)
cleaner not only cleans the air; it
helps to stop flames if the engine
backfires. Use caution when
working on the engine and do not
drive with the air cleaner/filter off.
Caution
If the air cleaner/filter is off, dirt
can easily get into the engine,
which could damage it. Always
have the air cleaner/filter in place
when you are driving.
Cooling System
The cooling system allows the
engine to maintain the correct
working temperature.
2.5L L4 Engine
1. Engine Cooling Fan (Outof View)
2. Engine Coolant Surge Tank and Pressure Cap
3.6L V6 Engine
1. Engine Cooling Fan (Outof View)
2. Engine Coolant Surge Tank and Pressure Cap
{Warning
An electric engine cooling fan
under the hood can start up even
when the engine is not running
and can cause injury. Keep
hands, clothing, and tools away
from any underhood electric fan.