light GMC SIERRA DENALI 2015 Owners Manual

Black plate (71,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
Vehicle Care 10-71brakes, rollover airbags, traction
control, electronic stability control,
or All-Wheel Drive, the performance
of these systems can also be
affected.
{ WarningIf different sized wheels are used,
there may not be an acceptable
level of performance and safety if
tires not recommended for those
wheels are selected. This
increases the chance of a crash
and serious injury. Only use GM
specific wheel and tire systems
developed for the vehicle, and
have them properly installed by a
GM certified technician.
See Buying New Tires on
page 10-69 and Accessories and
Modifications on page 10-3 .Uniform Tire Quality
Grading Quality grades can be found
where applicable on the tire
sidewall between tread shoulder
and maximum section width. For
example:
Treadwear 200 Traction AA
Temperature A
The following information relates
to the system developed by the
United States National Highway
Traffic Safety Administration
(NHTSA), which grades tires by
treadwear, traction, and
temperature performance. This
applies only to vehicles sold in
the United States. The grades
are molded on the sidewalls of
most passenger car tires. The
Uniform Tire Quality Grading
(UTQG) system does not apply
to deep tread, winter tires,
compact spare tires, tires with nominal rim diameters of
10 to 12 inches (25 to 30 cm),
or to some limited-production
tires.
While the tires available on
General Motors passenger cars
and light trucks may vary with
respect to these grades, they
must also conform to federal
safety requirements and
additional General Motors Tire
Performance Criteria (TPC)
standards.
All Passenger Car Tires Must
Conform to Federal Safety
Requirements In Addition To
These Grades.
Treadwear
The treadwear grade is a
comparative rating based on the
wear rate of the tire when tested
under controlled conditions on a
specified government test
course. For example, a tire

Black plate (72,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
10-72 Vehicle Care graded 150 would wear one and
one-half (1½) times as well on
the government course as a tire
graded 100. The relative
performance of tires depends
upon the actual conditions of
their use, however, and may
depart significantly from the
norm due to variations in driving
habits, service practices and
differences in road
characteristics and climate.
Traction
The traction grades, from
highest to lowest, are AA, A, B,
and C. Those grades represent
the tire's ability to stop on wet
pavement as measured under
controlled conditions on
specified government test
surfaces of asphalt and
concrete. A tire marked C may
have poor traction performance.
Warning: The traction grade
assigned to this tire is based on straight-ahead braking traction
tests, and does not include
acceleration, cornering,
hydroplaning, or peak traction
characteristics.
Temperature
The temperature grades are A
(the highest), B, and C,
representing the tire's resistance
to the generation of heat and its
ability to dissipate heat when
tested under controlled
conditions on a specified indoor
laboratory test wheel. Sustained
high temperature can cause the
material of the tire to degenerate
and reduce tire life, and
excessive temperature can lead
to sudden tire failure. The grade
C corresponds to a level of
performance which all
passenger car tires must meet
under the Federal Motor Safety
Standard No. 109. Grades B and
A represent higher levels of performance on the laboratory
test wheel than the minimum
required by law. Warning: The
temperature grade for this tire is
established for a tire that is
properly inflated and not
overloaded. Excessive speed,
underinflation, or excessive
loading, either separately or in
combination, can cause heat
buildup and possible tire failure.
Wheel Alignment and Tire
Balance The tires and wheels were aligned
and balanced at the factory to
provide the longest tire life and best
overall performance. Adjustments to
wheel alignment and tire balancing
are not necessary on a regular
basis. Consider an alignment check
if there is unusual tire wear or the
vehicle is significantly pulling to one
side or the other. Some slight pull to
the left or right, depending on the
crown of the road and/or other road

Black plate (89,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
Vehicle Care 10-89
{ WarningUsing an open flame near a
battery can cause battery gas to
explode. People have been hurt
doing this, and some have been
blinded. Use a flashlight if you
need more light.
Be sure the battery has enough
water. You do not need to add
water to the battery installed in
your new vehicle. But if a battery
has filler caps, be sure the right
amount of fluid is there. If it is low,
add water to take care of that
first. If you do not, explosive gas
could be present.
Battery fluid contains acid that
can burn you. Do not get it on
you. If you accidentally get it in
your eyes or on your skin, flush
the place with water and get
medical help immediately. { WarningFans or other moving engine
parts can injure you badly. Keep
your hands away from moving
parts once the engine is running.
6. Check that the jumper cables do
not have loose or missing
insulation. If they do, you could
get a shock. The vehicles could
be damaged too.
Before you connect the cables,
here are some basic things you
should know. Positive (+) will go
to positive (+) or to a remote
positive (+) terminal if the
vehicle has one. Negative ( − )
will go to a heavy, unpainted
metal engine part or to a remote
negative ( − ) terminal if the
vehicle has one.
Do not connect positive (+) to
negative ( − ) or you will get a
short that would damage the
battery and maybe other parts too. And do not connect the
negative ( − ) cable to the
negative ( − ) terminal on the
dead battery because this can
cause sparks.
5.3L Shown, 6.0L, 6.2L, and 6.6L
Similar
7. Connect the red positive (+)
cable to the positive (+) terminal
of the vehicle with the dead
battery.
8. Do not let the other end touch
metal. Connect it to the
positive (+) terminal of the good

Black plate (96,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
10-96 Vehicle Care 2. Set the parking brake. See
Parking Brake on page 9-47 .
3. Put the transmission in P (Park).
4. Secure the vehicle to the dolly
following the manufacturer's
instructions.
5. Use a clamping device designed
for towing to ensure that the
front wheels are locked into the
straight position.
6. Turn the ignition to LOCK/OFF.
Four-Wheel-Drive Vehicles
{ Warning
Shifting a four-wheel-drive
vehicle's transfer case into
N (Neutral) can cause the vehicle
to roll even if the transmission is
in P (Park). You or others could
be injured. Set the parking brake
before shifting the transfer case
to N (Neutral). To dolly tow a four-wheel-drive
vehicle from the rear:
1. Drive the rear wheels onto the
dolly.
2. Set the parking brake. See
Parking Brake on page 9-47 .
3. Put the transmission in P (Park).
4. Secure the vehicle to the dolly
following the manufacturer's
instructions.
5. Use a clamping device designed
for towing to ensure that the
front wheels are locked into the
straight position.
6. Shift the transfer case to
N (Neutral). See “ Shifting into
Neutral ” under Four-Wheel Drive
on page 9-40 for the proper
procedure.
7. Turn the ignition to LOCK/OFF. Appearance Care Exterior Care Locks Locks are lubricated at the factory.
Use a de-icing agent only when
absolutely necessary, and have the
locks greased after using. See
Recommended Fluids and
Lubricants on page 11-12 .
Washing the Vehicle To preserve the vehicle's finish,
wash it often and out of direct
sunlight.
{ Caution
Do not use petroleum-based,
acidic, or abrasive cleaning
agents as they can damage the
vehicle's paint, metal, or plastic
parts. If damage occurs, it would
not be covered by the vehicle
warranty. Approved cleaning
(Continued)

Black plate (103,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
Vehicle Care 10-103Coated Moldings Coated moldings should be cleaned. .
When lightly soiled, wipe with a
sponge or soft lint-free cloth
dampened with water. .
When heavily soiled, use warm
soapy water.
Fabric/Carpet/Suede Start by vacuuming the surface
using a soft brush attachment. If a
rotating brush attachment is being
used during vacuuming, only use it
on the floor carpet. Before cleaning,
gently remove as much of the soil
as possible using one of the
following techniques: .
Gently blot liquids with a paper
towel. Continue blotting until no
more soil can be removed. .
For solid soils, remove as much
as possible prior to vacuuming. To clean:
1. Saturate a clean lint-free
colorfast cloth with water.
Microfiber cloth is recommended
to prevent lint transfer to the
fabric or carpet.
2. Remove excess moisture by
gently wringing until water does
not drip from the cleaning cloth.
3. Start on the outside edge of the
soil and gently rub toward the
center. Rotate the cleaning cloth
to a clean area frequently to
prevent forcing the soil in to the
fabric.
4. Continue gently rubbing the
soiled area until there is no
longer any color transfer from
the soil to the cleaning cloth.
5. If the soil is not completely
removed, use a mild soap
solution followed only by plain
water.
If the soil is not completely
removed, it may be necessary to
use a commercial upholstery cleaner or spot lifter. Test a small
hidden area for colorfastness before
using a commercial upholstery
cleaner or spot lifter. If ring
formation occurs, clean the entire
fabric or carpet.
Following the cleaning process, a
paper towel can be used to blot
excess moisture.
Cleaning High Gloss Surfaces
and Vehicle Information and
Radio Displays For vehicles with high gloss
surfaces or vehicle displays, use a
microfiber cloth to wipe surfaces.
Before wiping the surface with the
microfiber cloth, use a soft bristle
brush to remove dirt that could
scratch the surface. Then use the
microfiber cloth by gently rubbing to
clean. Never use window cleaners
or solvents. Periodically hand wash
the microfiber cloth separately,
using mild soap. Do not use bleach
or fabric softener. Rinse thoroughly
and air dry before next use.

Black plate (9,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
Service and Maintenance 11-9
Additional
Maintenance and Care Your vehicle is an important
investment and caring for it properly
may help to avoid future costly
repairs. To maintain vehicle
performance, additional
maintenance services may be
required.
It is recommended that your dealer
perform these services — their
trained dealer technicians know
your vehicle best. Your dealer can
also perform a thorough
assessment with a multi-point
inspection to recommend when your
vehicle may need attention.
The following list is intended to
explain the services and conditions
to look for that may indicate
services are required. Battery
The battery supplies power to start
the engine and operate any
additional electrical accessories. .
To avoid break-down or failure to
start the vehicle, maintain a
battery with full cranking power. .
Trained dealer technicians have
the diagnostic equipment to test
the battery and ensure that the
connections and cables are
corrosion-free.
Belts .
Belts may need replacing if they
squeak or show signs of
cracking or splitting. .
Trained dealer technicians have
access to tools and equipment
to inspect the belts and
recommend adjustment or
replacement when necessary. Brakes
Brakes stop the vehicle and are
crucial to safe driving. .
Signs of brake wear may include
chirping, grinding, or squealing
noises, or difficulty stopping. .
Trained dealer technicians have
access to tools and equipment
to inspect the brakes and
recommend quality parts
engineered for the vehicle.
Fluids
Proper fluid levels and approved
fluids protect the vehicle ’ s systems
and components. See
Recommended Fluids and
Lubricants on page 11-12 for GM
approved fluids. .
Engine oil and windshield
washer fluid levels should be
checked at every fuel fill. .
Instrument cluster lights may
come on to indicate that fluids
may be low and need to be
filled.

Black plate (10,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
11-10 Service and Maintenance Hoses
Hoses transport fluids and should
be regularly inspected to ensure
that there are no cracks or leaks.
With a multi-point inspection, your
dealer can inspect the hoses and
advise if replacement is needed.
Lamps
Properly working headlamps,
taillamps, and brake lamps are
important to see and be seen on
the road. .
Signs that the headlamps need
attention include dimming, failure
to light, cracking, or damage.
The brake lamps need to be
checked periodically to ensure
that they light when braking. .
With a multi-point inspection,
your dealer can check the lamps
and note any concerns. Shocks and Struts
Shocks and struts help aid in control
for a smoother ride. .
Signs of wear may include
steering wheel vibration, bounce/
sway while braking, longer
stopping distance, or uneven
tire wear. .
As part of the multi-point
inspection, trained dealer
technicians can visually inspect
the shocks and struts for signs
of leaking, blown seals,
or damage, and can advise
when service is needed.
Tires
Tires need to be properly inflated,
rotated, and balanced. Maintaining
the tires can save money and fuel,
and can reduce the risk of tire
failure. .
Signs that the tires need to be
replaced include three or more
visible treadwear indicators; cord
or fabric showing through the rubber; cracks or cuts in the
tread or sidewall; or a bulge or
split in the tire. .
Trained dealer technicians can
inspect and recommend the right
tires. Your dealer can also
provide tire/wheel balancing
services to ensure smooth
vehicle operation at all speeds.
Your dealer sells and services
name brand tires.
Vehicle Care
To help keep the vehicle looking like
new, vehicle care products are
available from your dealer. For
information on how to clean and
protect the vehicle ’ s interior and
exterior, see Interior Care on
page 10-101 and Exterior Care on
page 10-96 .

Black plate (1,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
OnStar 14-1
OnStar OnStar Overview OnStar Overview . . . . . . . . . . . . 14-1
OnStar Services Emergency . . . . . . . . . . . . . . . . . . 14-2
Security . . . . . . . . . . . . . . . . . . . . . . 14-3
Navigation . . . . . . . . . . . . . . . . . . . 14-3
Connections . . . . . . . . . . . . . . . . . 14-4
Vehicle Diagnostics . . . . . . . . . . 14-6
OnStar Additional Information OnStar Additional
Information . . . . . . . . . . . . . . . . . 14-6 OnStar Overview
= Voice Command Button
Q Blue OnStar Button
> Emergency Button
This vehicle may be equipped with a
comprehensive, in-vehicle system
that can connect to a live OnStar
Advisor for Emergency, Security,
Navigation, Connection, and
Diagnostic Services. OnStar
services may require a paid
subscription. OnStar requires the
vehicle battery and electrical
system, cellular service, and GPS
satellite signals to be available and
operating. OnStar acts as a link to
existing public emergency service
providers. OnStar may collect
information about you and your vehicle, including location
information. See OnStar ’ s Terms
and Conditions and Privacy
Statement for more details including
system limitations at
www.onstar.com (U.S.) or
www.onstar.ca (Canada).
The OnStar system status light is
next to the OnStar buttons. If the
status light is: .
Solid Green: System is on. .
Flashing Green: On a call. .
Red: Indicates a problem. .
Off: System is off. Press the blue
OnStar button twice to speak
with an OnStar Advisor.
Press
Q or call 1-888-4-ONSTAR
(1-888-466-7827) to speak to an
Advisor.
Press
= to: .
Make a call, end a call,
or answer an incoming call. .
Give OnStar Hands-Free Calling
voice commands.

Black plate (4,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
14-4 OnStar navigation system in the vehicle (if
equipped). After the call ends, press
the “ Go ” button on the navigation
screen to begin driving directions.
If directions are downloaded to the
navigation system, the route can
only be canceled through the
navigation system.
Destinations can also be
downloaded on the go. For
information about eNav or
Destination Download, see
www.onstar.com (U.S.) or
www.onstar.ca (Canada).
Connections The required specific Onstar
subscription plan includes the
services that follow to help
customers stay connected.
For coverage maps, see
www.onstar.com (U.S.) or
www.onstar.ca (Canada). WiFi Connectivity (If Equipped)
The vehicle has a WiFi hotspot that
provides a high-speed, wireless
Internet connection to connect
multiple mobile devices (data plan
required).
1. To retrieve WiFi hotspot
information, press
= and select
or say “ WiFi settings. ”
2. The WiFi settings will display the
WiFi network name/SSID,
passphrase, and level of
encryption.
3. To change the SSID or
passphrase, press
Q or call
1-888-4-ONSTAR to connect
with an Advisor.
OnStar RemoteLink ®
Mobile App
(If Equipped)
Download the OnStar RemoteLink
mobile app to select Apple ®
,
Android ™ , and BlackBerry ®
or
Windows 7 or 8 mobile devices.
From the mobile device, check the
vehicle ’ s fuel level, oil life, or tire pressure (if the vehicle is equipped
with the tire pressure monitoring
system); or activate remote horn
and lights. Also remote start the
vehicle (if factory equipped) or
unlock the doors from anywhere
with a wireless connection (if
equipped with automatic locks).
With a required specific OnStar
subscription plan, a destination can
be sent to the vehicle. For OnStar
RemoteLink information and
compatibility, see www.onstar.com
(U.S.) or www.onstar.ca (Canada).
OnStar RemoteLink ®
Key Fob
Services
This feature is included for five
years and allows for remote door
lock/unlock (if equipped with
automatic locks), remote start (if
factory equipped), or activation of
horn and lights from anywhere with
a wireless signal. Download the app
and start using it any time during the
trial period to get started.

Black plate (1,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
INDEX i-1
AAccessories and
Modifications . . . . . . . . . . . . . . . . . 10-3
Accessory Power . . . . . . . . . . . . . . 9-29
Active Fuel Management ®
. . . . . 9-32
Add-On Electrical
Equipment . . . . . . . . . . . . . . . . . . . 9-88
Adding a Snow Plow or
Similar Equipment . . . . . . . . . . . . 9-88
Additional Information
OnStar ®
. . . . . . . . . . . . . . . . . . . . . . 14-6
Additional Maintenance
and Care . . . . . . . . . . . . . . . . . . . . . 11-9
Adjustable Throttle and
Brake Pedal . . . . . . . . . . . . . . . . . . 9-23
Adjustments
Lumbar, Front Seats . . . . . . . . . . . 3-3
Air Cleaner/Filter, Engine . . . . . 10-15
Air Filter, Passenger
Compartment . . . . . . . . . . . . . . . . . 8-5
Air Vents . . . . . . . . . . . . . . . . . . . . . . . 8-4 Airbag System
Check . . . . . . . . . . . . . . . . . . . . . . . . 3-29
How Does an Airbag
Restrain? . . . . . . . . . . . . . . . . . . . 3-22
Passenger Sensing
System . . . . . . . . . . . . . . . . . . . . . . 3-24
What Makes an Airbag
Inflate? . . . . . . . . . . . . . . . . . . . . . . 3-22
What Will You See after an
Airbag Inflates? . . . . . . . . . . . . . 3-22
When Should an Airbag
Inflate? . . . . . . . . . . . . . . . . . . . . . . 3-20
Where Are the Airbags? . . . . . . 3-18
Airbags
Adding Equipment to the
Vehicle . . . . . . . . . . . . . . . . . . . . . . 3-28
Passenger Status Indicator . . . 5-17
Readiness Light . . . . . . . . . . . . . . 5-16
Servicing Airbag-Equipped
Vehicles . . . . . . . . . . . . . . . . . . . . . 3-28
System Check . . . . . . . . . . . . . . . . 3-17
Alarm
Vehicle Security . . . . . . . . . . . . . . 2-11
All-Season Tires . . . . . . . . . . . . . . 10-51
All-Terrain Tires . . . . . . . . . . . . . . . 10-52 Antilock Brake
System (ABS) . . . . . . . . . . . . . . . . 9-46
Warning Light . . . . . . . . . . . . . . . . . 5-21
Appearance Care
Exterior . . . . . . . . . . . . . . . . . . . . . 10-96
Interior . . . . . . . . . . . . . . . . . . . . . 10-101
Assistance Program,
Roadside . . . . . . . . . . . . . . . . . . . . . 13-5
Assistance Systems for
Driving . . . . . . . . . . . . . . . . . . . . . . . 9-59
Assistance Systems for
Parking and Backing . . . . . . . . . 9-56
Automatic
Dimming Mirrors . . . . . . . . . . . . . . 2-17
Door Locks . . . . . . . . . . . . . . . . . . . . 2-9
Headlamp System . . . . . . . . . . . . . 6-3
Transmission . . . . . . . . . . . . . . . . . 9-33
Transmission Fluid . . 10-12, 10-15
Automatic Transmission
Manual Mode . . . . . . . . . . . . . . . . . 9-36
Shift Lock Control
Function Check . . . . . . . . . . . 10-34
Auxiliary
Roof Mounted Lamp . . . . . . . . . . . 6-5
Axle, Front . . . . . . . . . . . . . . . . . . . . 10-30
Axle, Rear . . . . . . . . . . . . . . . . . . . . 10-31