brake GMC ACADIA 2018 Repair Manual

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 277
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) must be
equipped with its own brake system,
with brakes working on all axles.
Trailer braking equipment
conforming to Canadian Standards
Association (CSA) requirement
CAN3-D313, or its equivalent, is
recommended.
State and local regulations may also
require the trailer to have its own
braking system if loaded above a
certain threshold. These
requirements vary from state to
state.
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 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.
Electric Trailer Brake Control
Wiring Provisions
These wiring provisions for an
electric trailer brake controller are
included with the vehicle as part of

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
Vehicle Care 279
Vehicle Care
General Information
General Information . . . . . . . . . . 280
California Proposition65 Warning . . . . . . . . . . . . . . . . . 280
California Perchlorate Materials Requirements . . . . . 281
Accessories and Modifications . . . . . . . . . . . . . . . . 281
Vehicle Checks
Doing Your OwnService Work . . . . . . . . . . . . . . . 281
Hood . . . . . . . . . . . . . . . . . . . . . . . . . 282
Engine Compartment Overview . . . . . . . . . . . . . . . . . . . . 283
Engine Oil . . . . . . . . . . . . . . . . . . . . 286
Engine Oil Life System . . . . . . . 288
Automatic Transmission Fluid . . . . . . . . . . . . . . . . . . . . . . . . 289
Engine Air Cleaner/Filter . . . . . . 290
Cooling System . . . . . . . . . . . . . . 291
Engine Overheating . . . . . . . . . . 295
Washer Fluid . . . . . . . . . . . . . . . . . 296
Brakes . . . . . . . . . . . . . . . . . . . . . . . 297
Brake Fluid . . . . . . . . . . . . . . . . . . . 298
Battery - North America . . . . . . 299
All-Wheel Drive . . . . . . . . . . . . . . . 300 Starter Switch Check . . . . . . . . . 300
Automatic Transmission Shift
Lock Control Function
Check . . . . . . . . . . . . . . . . . . . . . . . 300
Park Brake and P (Park)
Mechanism Check . . . . . . . . . . 300
Wiper Blade Replacement . . . . 301
Windshield Replacement . . . . . 302
Gas Strut(s) . . . . . . . . . . . . . . . . . . 302
Headlamp Aiming
Headlamp Aiming . . . . . . . . . . . . 303
Bulb Replacement
Bulb Replacement . . . . . . . . . . . . 304
Halogen Bulbs . . . . . . . . . . . . . . . . 304
LED Lighting . . . . . . . . . . . . . . . . . 304
License Plate Lamp . . . . . . . . . . 304
Electrical System
High Voltage Devices and Wiring . . . . . . . . . . . . . . . . . . . . . . . 305
Electrical System Overload . . . 305
Fuses and Circuit Breakers . . . 306
Engine Compartment Fuse Block . . . . . . . . . . . . . . . . . . . . . . . . 306
Instrument Panel Fuse Block . . . . . . . . . . . . . . . . . . . . . . . . 309
Rear Compartment Fuse Block . . . . . . . . . . . . . . . . . . . . . . . . 311
Wheels and Tires
Tires . . . . . . . . . . . . . . . . . . . . . . . . . . 314
All-Season Tires . . . . . . . . . . . . . . 315
Winter Tires . . . . . . . . . . . . . . . . . . 315
Summer Tires . . . . . . . . . . . . . . . . 315
Tire Sidewall Labeling . . . . . . . . 316
Tire Designations . . . . . . . . . . . . . 318
Tire Terminology andDefinitions . . . . . . . . . . . . . . . . . . 319
Tire Pressure . . . . . . . . . . . . . . . . . 321
Tire Pressure for High-Speed Operation . . . . . . . . . . . . . . . . . . . 323
Tire Pressure Monitor System . . . . . . . . . . . . . . . . . . . . . . 323
Tire Pressure Monitor Operation . . . . . . . . . . . . . . . . . . . 324
Tire Inspection . . . . . . . . . . . . . . . . 328
Tire Rotation . . . . . . . . . . . . . . . . . 328
When It Is Time for New Tires . . . . . . . . . . . . . . . . . . . . . . . . 329
Buying New Tires . . . . . . . . . . . . . 330
Different Size Tires and Wheels . . . . . . . . . . . . . . . . . . . . . . 332
Uniform Tire Quality Grading . . . . . . . . . . . . . . . . . . . . . 332
Wheel Alignment and Tire Balance . . . . . . . . . . . . . . . . . . . . . 333
Wheel Replacement . . . . . . . . . . 334
Tire Chains . . . . . . . . . . . . . . . . . . . 334
If a Tire Goes Flat . . . . . . . . . . . . 335

GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349114) - 2018 - crc - 9/21/17
Vehicle Care 281
California Perchlorate
Materials Requirements
Certain types of automotive
applications, such as airbag
initiators, seat belt pretensioners,
and lithium batteries contained in
Remote Keyless Entry transmitters,
may contain perchlorate materials.
Special handling may be necessary.
For additional information, 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 090.
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 Service
Publications Ordering Information
0 393.
This vehicle has an airbag system.
Before attempting to do your own
service work, see Servicing the
Airbag-Equipped Vehicle 089.

GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349114) - 2018 - crc - 9/21/17
284 Vehicle Care
1.Engine Air Cleaner/Filter 0290.
2. Engine Oil Fill Cap. See Engine Oil 0286.
3. Engine Oil Dipstick. See Engine Oil 0286.
4. Engine Cooling Fan (Out of View). See Cooling System
0 291.
5. Windshield Washer Fluid Reservoir. See Washer Fluid
0 296.
6. Brake Fluid Reservoir. See Brake Fluid 0298.
7. Battery - North America 0299.
8. Engine Coolant Surge Tank and Pressure Cap. See
Cooling System 0291.
9. Positive (+) Battery Terminal (Under Cover). See Jump
Starting - North America 0351.
10. Engine Compartment Fuse
Block 0306.
11. Remote Negative (-) Battery Terminal. See Jump Starting -
North America 0351.

GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349114) - 2018 - crc - 9/21/17
286 Vehicle Care
1.Engine Air Cleaner/Filter 0290.
2. Engine Oil Fill Cap. See Engine Oil 0286.
3. Engine Oil Dipstick. See Engine Oil 0286.
4. Engine Cooling Fan (Out of View). See Cooling System
0 291.
5. Windshield Washer Fluid Reservoir. See Washer Fluid
0 296.
6. Brake Fluid Reservoir. See Brake Fluid 0298.
7. Battery - North America 0299.
8. Engine Coolant Surge Tank and Pressure Cap. See
Cooling System 0291.
9. Positive (+) Battery Terminal. See Jump Starting - North
America 0351.
10. Engine Compartment Fuse
Block 0306.
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 0288.
. 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
0283 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

GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349114) - 2018 - crc - 9/21/17
Vehicle Care 297
Caution (Continued)
.When using concentrated
washer fluid, follow the
manufacturer instructions for
adding water.
. Fill the washer fluid tank
only three-quarters full when
it is very cold. This allows
for fluid expansion if
freezing occurs, which could
damage the tank if it is
completely full.
Brakes
Disc brake pads have built-in wear
indicators that make a high-pitched
warning sound when the brake pads
are worn and new pads are needed.
The sound can come and go or can
be heard all the time when the
vehicle is moving, except when
applying the brake pedal firmly.
{Warning
The brake wear warning sound
means that soon the brakes will
not work well. That could lead to
a crash. When the brake wear
warning sound is heard, have the
vehicle serviced.
Caution
Continuing to drive with worn-out
brake pads could result in costly
brake repair.
Some driving conditions or climates
can cause a brake squeal when the
brakes are first applied or lightly
applied. This does not mean
something is wrong with the brakes.
Properly torqued wheel nuts are
necessary to help prevent brake
pulsation. When tires are rotated,
inspect brake pads for wear and
evenly tighten wheel nuts in the proper sequence to torque
specifications. See
Capacities and
Specifications 0381.
Brake pads should be replaced as
complete sets.
Brake Pedal Travel
See your dealer if the brake pedal
does not return to normal height,
or if there is a rapid increase in
pedal travel. This could be a sign
that brake service may be required.
Replacing Brake System Parts
Always replace brake system parts
with new, approved replacement
parts. If this is not done, the brakes
may not work properly. The braking
performance expected can change
in many other ways if the wrong
replacement brake parts are
installed or if parts are improperly
installed.

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.