
Black plate (69,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
Vehicle Care 10-69driving. When storing a vehicle for
at least a month, remove the tires or
raise the vehicle to reduce the
weight from the tires.
Buying New Tires GM has developed and matched
specific tires for the vehicle. The
original equipment tires installed
were designed to meet General
Motors Tire Performance Criteria
Specification (TPC Spec)
system rating. When
replacement tires are needed,
GM strongly recommends
buying tires with the same TPC
Spec rating.
GM's exclusive TPC Spec
system considers over a dozen
critical specifications that impact
the overall performance of the
vehicle, including brake system
performance, ride and handling,
traction control, and tire
pressure monitoring
performance. GM's TPC Spec number is molded onto the tire's
sidewall near the tire size. If the
tires have an all-season tread
design, the TPC Spec number
will be followed by MS for mud
and snow. See Tire Sidewall
Labeling on page 10-52 for
additional information.
GM recommends replacing worn
tires in complete sets of four (six
for dual rear wheels). Uniform
tread depth on all tires will help
to maintain the performance of
the vehicle. Braking and
handling performance may be
adversely affected if all the tires
are not replaced at the same
time. If proper rotation and
maintenance have been done,
all four tires (six for dual rear
wheels) should wear out at
about the same time. See Tire
Rotation on page 10-65 for
information on proper tire
rotation. However, if it is
necessary to replace only one axle set of worn tires, place the
new tires on the rear axle (two
for single rear wheels, four for
dual rear wheels).
{ Warning
Tires could explode during
improper service. Attempting
to mount or dismount a tire
could cause injury or death.
Only your dealer or authorized
tire service center should
mount or dismount the tires.
{ Warning
Mixing tires of different sizes,
brands, or types may cause
loss of control of the vehicle,
resulting in a crash or other
(Continued)

Black plate (70,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
10-70 Vehicle Care Warning (Continued)
vehicle damage. Use the
correct size, brand, and type
of tires on all wheels.
This vehicle may have a
different size spare than the
road tires originally installed
on the vehicle. When new, the
vehicle included a spare tire
and wheel assembly with a
similar overall diameter as the
road tires and wheels, so it is
all right to drive on it. The
spare tire was developed for
use on this vehicle and will not
affect vehicle handling.
{ Warning
Using bias-ply tires on the
vehicle may cause the wheel
rim flanges to develop cracks
(Continued) Warning (Continued)
after many miles of driving.
A tire and/or wheel could fail
suddenly and cause a crash.
Use only radial-ply tires with
the wheels on the vehicle.
Winter tires with the same speed
rating as the original equipment
tires may not be available for H,
V, W, Y and ZR speed rated
tires. Never exceed the winter
tires ’ maximum speed capability
when using winter tires with a
lower speed rating.
If the vehicle tires must be
replaced with a tire that does not
have a TPC Spec number, make
sure they are the same size,
load range, speed rating, and
construction (radial) as the
original tires. Vehicles that have a tire
pressure monitoring system
could give an inaccurate
low-pressure warning if non-TPC
Spec rated tires are installed.
See Tire Pressure Monitor
System on page 10-61 .
The Tire and Loading
Information label indicates the
original equipment tires on the
vehicle. See Vehicle Load Limits
on page 9-15 for the label
location and more information
about the Tire and Loading
Information label.
Different Size Tires and
Wheels If wheels or tires are installed that
are a different size than the original
equipment wheels and tires, vehicle
performance, including its braking,
ride and handling characteristics,
stability, and resistance to rollover
may be affected. If the vehicle has
electronic systems such as antilock

Black plate (73,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
Vehicle Care 10-73surface variations such as troughs
or ruts, is normal. If the vehicle is
vibrating when driving on a smooth
road, the tires and wheels may need
to be rebalanced. See your dealer
for proper diagnosis.
Wheel Replacement Replace any wheel that is bent,
cracked, or badly rusted or
corroded. If wheel nuts keep coming
loose, the wheel, wheel bolts and
wheel nuts should be replaced.
If the wheel leaks air, replace it.
Some aluminum wheels can be
repaired. See your dealer if any of
these conditions exist.
Your dealer will know the kind of
wheel that is needed.
Each new wheel should have the
same load-carrying capacity,
diameter, width, offset and be
mounted the same way as the one it
replaces. Replace wheels, wheel bolts, wheel
nuts, or Tire Pressure Monitor
System (TPMS) sensors with new
GM original equipment parts.
{ WarningUsing the wrong replacement
wheels, wheel bolts, or wheel
nuts can be dangerous. It could
affect the braking and handling of
the vehicle. Tires can lose air,
and cause loss of control, causing
a crash. Always use the correct
wheel, wheel bolts, and wheel
nuts for replacement.
{ Caution
The wrong wheel can also cause
problems with bearing life, brake
cooling, speedometer or
odometer calibration, headlamp
aim, bumper height, vehicle
(Continued) Caution (Continued) ground clearance, and tire or tire
chain clearance to the body and
chassis.
Whenever a wheel, wheel bolt,
or wheel nut is replaced on a dual
wheel setup, check the wheel nut
torque after 160, 1 600 and
10 000 km (100, 1,000 and 6,000 mi)
of driving. For proper torque, see
“ Wheel Nut Torque ” under
Capacities and Specifications on
page 12-2 .
See If a Tire Goes Flat on
page 10-74 for more information.
Used Replacement Wheels
{ Warning
Replacing a wheel with a used
one is dangerous. How it has
been used or how far it has been
(Continued)

Black plate (86,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
10-86 Vehicle Care To store the jack and jack tools:
1. Wing Nut Retaining Wheel
Blocks
2. Wheel Blocks
3. Wing Nut Retaining Tool Kit
4. Wheel Wrench and
Extensions
5. Tool Bag
6. Jack Mounting Bracket
7. Jack
8. Bolt Retaining Wheel Blocks
1. Put the tools (4) in the tool
bag (5) and place them in the
retaining bracket (3). 2. Tighten down the wing nut (3).
3. Assemble the wheel blocks (2)
and jack (7) together with the
wing nut (1) and retaining
bolt (8).
4. Position the jack (7) in the
mounting bracket (6). Position
the holes in the base of the
jack (7) onto the pin in the
mounting bracket (6).
5. Return them to their original
location in the vehicle. See
“ Removing the Spare Tire and
Tools. ”
Full-Size Spare Tire If this vehicle came with a full-size
spare tire, it was fully inflated when
new, however, it can lose air over
time. Check the inflation pressure
regularly. See Tire Pressure on
page 10-59 and Vehicle Load Limits
on page 9-15 . For instructions on
how to remove, install, or store a
spare tire, see Tire Changing on
page 10-76 . If equipped with a temporary use
full-size spare tire, it is indicated on
the tire sidewall. See Tire Sidewall
Labeling on page 10-52 . This spare
tire should not be driven on over
112 km/h (70 mph), or 88 km/h
(55 mph) when pulling a trailer, at
the proper inflation pressure.
Repair and replace the road tire as
soon as it is convenient, and stow
the spare tire for future use.
{ CautionIf the vehicle has four-wheel drive
and a different size spare tire is
installed, do not drive in
four-wheel drive until the flat tire
is repaired and/or replaced. The
vehicle could be damaged and
the repairs would not be covered
by the warranty. Never use
four-wheel drive when a different
size spare tire is installed on the
vehicle.

Black plate (3,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
Service and Maintenance 11-3
Maintenance
Schedule Owner Checks and Services At Each Fuel Stop .
Check the engine oil level. See
Engine Oil on page 10-8 .
Once a Month .
Check the tire inflation
pressures. See Tire Pressure on
page 10-59 ..
Inspect the tires for wear. See
Tire Inspection on page 10-65 ..
Check the windshield washer
fluid level. See Washer Fluid on
page 10-25 .
Engine Oil Change
When the CHANGE ENGINE OIL
SOON message displays, have the
engine oil and filter changed within
the next 1 000 km/600 mi. If driven
under the best conditions, the
engine oil life system may not
indicate the need for vehicle service for up to a year. The engine oil and
filter must be changed at least once
a year and the oil life system must
be reset. Your trained dealer
technician can perform this work.
If the engine oil life system is reset
accidentally, service the vehicle
within 5 000 km/3,000 mi since the
last service. Reset the oil life
system when the oil is changed.
See Engine Oil Life System on
page 10-11 .
Passenger Compartment Air
Filter The passenger compartment air
filter removes dust, pollen, and
other airborne irritants from outside
air that is pulled into the vehicle.
The filter should be replaced as part
of routine scheduled maintenance.
Inspect the passenger compartment
air filter every 36 000 km/
22,500 miles or two years,
whichever comes first. Replace if
necessary. More frequent
replacement may be needed if the
vehicle is driven in areas with heavy traffic, areas with poor air quality,
or areas with high dust levels.
Replacement may also be needed if
there is a reduction in air flow,
excessive window fogging, or odors.
Tire Rotation and Required
Services Every 12 000 km/
7,500 mi Rotate the tires, if recommended for
the vehicle, and perform the
following services. See Tire
Rotation on page 10-65 . .
Check engine oil level and oil
life percentage. If needed,
change engine oil and filter, and
reset oil life system. See Engine
Oil on page 10-8 and Engine Oil
Life System on page 10-11 . .
Check engine coolant level. See
Engine Coolant on page 10-18 . .
Check windshield washer fluid
level. See Washer Fluid on
page 10-25 .

Black plate (4,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
11-4 Service and Maintenance .
Visually inspect windshield wiper
blades for wear, cracking,
or contamination. See Exterior
Care on page 10-96 . Replace
worn or damaged wiper blades.
See Wiper Blade Replacement
on page 10-35 ..
Check tire inflation pressures.
See Tire Pressure on
page 10-59 ..
Inspect tire wear. See Tire
Inspection on page 10-65 ..
Visually check for fluid leaks. .
Inspect engine air cleaner filter.
See Engine Air Cleaner/Filter on
page 10-15 ..
Inspect brake system. .
Visually inspect steering,
suspension, and chassis
components for damaged, loose,
or missing parts or signs of wear
at least once a year. See
Exterior Care on page 10-96 .
Lubricate the suspension and steering components at least
every other oil change.
(If equipped with grease fittings) .
Check restraint system
components. See Safety System
Check on page 3-16 . .
Visually inspect fuel system for
damage or leaks. .
Visually inspect exhaust system
and nearby heat shields for
loose or damaged parts. .
Lubricate body components. See
Exterior Care on page 10-96 ..
Check starter switch. See Starter
Switch Check on page 10-33 ..
Check automatic transmission
shift lock control function. See
Automatic Transmission Shift
Lock Control Function Check on
page 10-34 . .
Check ignition transmission lock.
See Ignition Transmission Lock
Check on page 10-34 . .
Check parking brake and
automatic transmission park
mechanism. See Park Brake and
P (Park) Mechanism Check on
page 10-34 . .
Check accelerator pedal for
damage, high effort, or binding.
Replace if needed. .
Visually inspect gas strut for
signs of wear, cracks, or other
damage. Check the hold open
ability of the strut. See your
dealer if service is required. .
Inspect sunroof track and seal,
if equipped. See Sunroof on
page 2-22 . .
Verify spare tire key lock
operation and lubricate as
needed. See Tire Changing on
page 10-76 .

Black plate (12,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
13-12 Customer Information Current and Past Models Technical Service Bulletins and
Manuals are available for current
and past model GM vehicles.
ORDER TOLL FREE:
1-800-551-4123 Monday – Friday
8:00 AM – 6:00 PM Eastern Time
For Credit Card Orders Only
(VISA-MasterCard-Discover), see
Helm, Inc. at: www.helminc.com.
Or write to:
Helm, Incorporated
Attention: Customer Service
47911 Halyard Drive
Plymouth, MI 48170
Prices are subject to change without
notice and without incurring
obligation. Allow ample time for
delivery.
All listed prices are quoted in U.S.
funds. Make checks payable in U.S.
funds. Radio Frequency
Identification (RFID) RFID technology is used in some
vehicles for functions such as tire
pressure monitoring and ignition
system security, as well as in
connection with conveniences such
as Remote Keyless Entry (RKE)
transmitters for remote door locking/
unlocking and starting, and
in-vehicle transmitters for garage
door openers. RFID technology in
GM vehicles does not use or record
personal information or link with any
other GM system containing
personal information.
Radio Frequency
Statement This vehicle has systems that
operate on a radio frequency that
complies with Part 15/Part 18 of the
Federal Communications
Commission (FCC) rules and with
Industry Canada Standards
RSS-GEN/210/220/310. Operation is subject to the following
two conditions:
1. The device may not cause
harmful interference.
2. The device must accept any
interference received, including
interference that may cause
undesired operation of the
device.
Changes or modifications to any of
these systems by other than an
authorized service facility could void
authorization to use this equipment.

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.