
GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349114) - 2018 - crc - 9/21/17
278 Driving and Operating
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) 0136.
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 089 and Adding Equipment
to the Airbag-Equipped Vehicle
0 90.

GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349114) - 2018 - crc - 9/21/17
282 Vehicle Care
Keep a record with all parts receipts
and list the mileage and the date of
any service work performed. See
Maintenance Records0379.
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-11349114) - 2018 - crc - 9/21/17
Vehicle Care 289
include engine revolutions, engine
temperature, and miles driven.
Based on driving conditions, the
mileage at which an oil change is
indicated can vary considerably. For
the oil life system to work properly,
the system must be reset every time
the oil is changed.
When the system has calculated
that oil life has been diminished, it
indicates that an oil change is
necessary. A CHANGE ENGINE
OIL SOON message comes on.
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)
0 145 orDriver Information
Center (DIC) (Uplevel) 0148.
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
0 369, 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
(Continued)

GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349114) - 2018 - crc - 9/21/17
290 Vehicle Care
Caution (Continued)
not be covered by the vehicle
warranty. Always use the
automatic transmission fluid listed
inRecommended Fluids and
Lubricants 0377.
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
0 283 for location.
When to Inspect the Engine Air
Cleaner/Filter
For intervals on changing and
inspecting the engine air cleaner/
filter, see Maintenance Schedule
0 369.
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.

GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349114) - 2018 - crc - 9/21/17
292 Vehicle Care
3.6L V6 Engine
1. Engine Cooling Fan (Outof View)
2. Engine Coolant Surge Tank and Pressure Cap
{Warning
An underhood electric fan 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.
{Warning
Do not touch heater or radiator
hoses, or other engine parts.
They can be very hot and can
burn you. Do not run the engine if
there is a leak; all coolant could
leak out. That could cause an
engine fire and can burn you. Fix
any leak before driving the
vehicle.
Engine Coolant
The cooling system in the vehicle is
filled with DEX-COOL engine
coolant. This coolant needs to be
checked and replaced at
appropriate intervals. See
Maintenance Schedule 0369.
The following explains the cooling
system and how to check and add
coolant when it is low. If there is a
problem with engine overheating,
see Engine Overheating 0295.
What to Use
{Warning
Do not touch heater or radiator
hoses, or other engine parts.
They can be very hot and can
burn you. Do not run the engine if
there is a leak; all coolant could
leak out. That could cause an
engine fire and can burn you. Fix
any leak before driving the
vehicle.
Use a 50/50 mixture of clean,
drinkable water and DEX-COOL
coolant. This mixture:
. Gives freezing protection down
to−37 °C (−34 °F), outside
temperature.
. Gives boiling protection up to
129 °C (265 °F), engine
temperature.
. Protects against rust and
corrosion.
. Will not damage aluminum parts.

GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349114) - 2018 - crc - 9/21/17
298 Vehicle Care
Brake Fluid
The brake master cylinder reservoir
is filled with GM approved DOT 3
brake fluid as indicated on the
reservoir cap. SeeEngine
Compartment Overview 0283 for
the location of the reservoir.
Checking Brake Fluid
With the vehicle in P (Park) on a
level surface, the brake fluid level
should be between the minimum
and maximum marks on the brake
fluid reservoir.
There are only two reasons why the
brake fluid level in the reservoir may
go down:
. Normal brake lining wear. When
new linings are installed, the
fluid level goes back up. .
A fluid leak in the brake
hydraulic system. Have the
brake hydraulic system fixed.
With a leak, the brakes will not
work well.
Always clean the brake fluid
reservoir cap and the area around
the cap before removing it.
Do not top off the brake fluid.
Adding fluid does not correct a leak.
If fluid is added when the linings are
worn, there will be too much fluid
when new brake linings are
installed. Add or remove fluid, as
necessary, only when work is done
on the brake hydraulic system.
{Warning
If too much brake fluid is added, it
can spill on the engine and burn,
if the engine is hot enough. You
or others could be burned, and
the vehicle could be damaged.
Add brake fluid only when work is
done on the brake hydraulic
system. When the brake fluid falls to a low
level, the brake warning light comes
on. See
Brake System Warning
Light 0138.
Brake fluid absorbs water over time
which degrades the effectiveness of
the brake fluid. Replace brake fluid
at the specified intervals to prevent
increased stopping distance. See
Maintenance Schedule 0369.
What to Add
Use only GM approved DOT 3
brake fluid from a clean, sealed
container. See Recommended
Fluids and Lubricants 0377.
{Warning
The wrong or contaminated brake
fluid could result in damage to the
brake system. This could result in
the loss of braking leading to a
possible injury. Always use the
proper GM approved brake fluid.

GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349114) - 2018 - crc - 9/21/17
Vehicle Care 299
Caution
If brake fluid is spilled on the
vehicle's painted surfaces, the
paint finish can be damaged.
Immediately wash off any painted
surface.
Battery - North America
The original equipment battery is
maintenance free. Do not remove
the cap and do not add fluid.
Refer to the replacement number on
the original battery label when a
new battery is needed. For
replacement of the battery, see your
dealer.
Stop/Start System
If equipped with the 2.5L L4 engine,
the vehicle has a stop/start system
to shut off the engine to help
conserve fuel. SeeStarting the
Engine 0223. It has an Absorbed Glass Mat
(AGM) 12-volt battery. Installation of
a standard 12-volt battery will result
in reduced 12-volt battery life.
When using a 12-volt battery
charger on the 12-volt AGM battery,
some chargers have an AGM
battery setting on the charger.
If available, use the AGM setting on
the charger, to limit charge voltage
to 14.8 volts.
{Warning
WARNING:
Battery posts,
terminals, and related
accessories contain lead and lead
compounds, chemicals known to
the State of California to cause
cancer and birth defects or other
reproductive harm. Batteries also
contain other chemicals known to
the State of California to cause
cancer. WASH HANDS AFTER
HANDLING. For more information
go to www.P65Warnings.ca.gov/
passenger-vehicle. See
California Proposition
65 Warning 0280 and the back
cover.
Vehicle Storage
{Warning
Batteries have acid that can burn
you and gas that can explode.
You can be badly hurt if you are
not careful. See Jump Starting -
North America 0351 for tips on
working around a battery without
getting hurt.
Infrequent Usage: Remove the
black, negative (−) cable from the
battery to keep the battery from
running down.
Extended Storage: Remove the
black, negative (−) cable from the
battery or use a battery trickle
charger.

GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349114) - 2018 - crc - 9/21/17
300 Vehicle Care
All-Wheel Drive
Transfer Case
Under normal driving conditions,
transfer case fluid does not require
maintenance unless there is a fluid
leak or unusual noise. If required,
have the transfer case serviced by
your dealer.
Starter Switch Check
{Warning
When you are doing this
inspection, the vehicle could
move suddenly. If the vehicle
moves, you or others could be
injured.
1. Before starting this check, be sure there is enough room
around the vehicle.
2. Apply both the parking brake and the regular brake. Do not use the accelerator
pedal, and be ready to turn off
the engine immediately if it
starts.
3. Try to start the engine in each gear. The vehicle should start
only in P (Park) or N (Neutral).
If the vehicle starts in any other
position, contact your dealer for
service.
Automatic Transmission
Shift Lock Control
Function Check
{Warning
When you are doing this
inspection, the vehicle could
move suddenly. If the vehicle
moves, you or others could be
injured.
1. Before starting this check, be sure there is enough room
around the vehicle. It should be
parked on a level surface. 2. Apply the parking brake. Be
ready to apply the regular
brake immediately if the vehicle
begins to move.
3. With the engine off, turn the ignition on, but do not start the
engine. Without applying the
regular brake, try to move the
shift lever out of P (Park) with
normal effort. If the shift lever
moves out of P (Park), contact
your dealer for service.
Park Brake and P (Park)
Mechanism Check
{Warning
When you are doing this check,
the vehicle could begin to move.
You or others could be injured
and property could be damaged.
Make sure there is room in front
of the vehicle in case it begins to
roll. Be ready to apply the regular
brake at once should the vehicle
begin to move.