
Black plate (4,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - CRC - 6/20/14
2-4 Keys, Doors, and Windows
Remote Keyless Entry
(RKE) System See Radio Frequency Statement on
page 13-12 .
If there is a decrease in the RKE
operating range: .
Check the distance. The
transmitter may be too far from
the vehicle. .
Check the location. Other
vehicles or objects may be
blocking the signal. .
Check the transmitter's battery.
See “ Battery Replacement ” later
in this section. .
If the transmitter is still not
working correctly, see your
dealer or a qualified technician
for service. Remote Keyless Entry
(RKE) System Operation The RKE transmitter functions may
work up to 60 m (197 ft) away from
the vehicle.
Other conditions can affect the
performance of the transmitter. See
Remote Keyless Entry (RKE)
System on page 2-4 .
With Remote Start (without
Remote Start Similar)
/ (Remote Vehicle Start):
If equipped,
/ is used to start the
engine from outside the vehicle
using the RKE transmitter. See
Remote Vehicle Start on page 2-7 .
Q (Lock): Press to lock all doors.
If enabled through the Driver
Information Center (DIC), the turn
signal lamps flash once to indicate
locking has occurred. If enabled
through the DIC, the horn chirps 

Black plate (6,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - CRC - 6/20/14
2-6 Keys, Doors, and Windows Battery Replacement Replace the battery in the
transmitter soon if the REPLACE
BATTERY IN REMOTE KEY
message displays in the DIC.
{ CautionWhen replacing the battery, do
not touch any of the circuitry on
the transmitter. Static from your
body could damage the
transmitter. To replace the battery:
1. Separate and remove the back
cover of the transmitter with a
flat, thin object, such as a coin. 2. Press and slide the battery down
toward the pocket of the
transmitter in the direction of the
key ring. Do not use a metal
object.
3. Remove the battery.
4. Insert the new battery, positive
side facing up. Replace with a
CR2032 or equivalent battery.
5. Push together the transmitter
back cover top side first, and
then the bottom toward the
key ring. 

Black plate (35,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
Instruments and Controls 5-35
Fuel System Messages FUEL LEVEL LOW This message displays and a chime
may sound if the fuel level is low.
Refuel as soon as possible. See
Fuel Gauge on page 5-12 and Fuel
on page 9-63 .
TIGHTEN GAS CAP This message may display along
with the malfunction indicator lamp
on the instrument cluster if the
vehicle's fuel cap is not tightened
properly. See Malfunction Indicator
Lamp on page 5-18 . Reinstall the
fuel cap fully. See Filling the Tank
on page 9-66 . The diagnostic
system can determine if the fuel cap
has been left off or improperly
installed. A loose or missing fuel
cap allows fuel to evaporate into the
atmosphere. A few driving trips with
the cap properly installed should
turn this light and message off. Key and Lock Messages REPLACE BATTERY IN
REMOTE KEY This message displays if a Remote
Keyless Entry (RKE) transmitter
battery is low. The battery needs to
be replaced in the transmitter. See
“ Battery Replacement ” under
Remote Keyless Entry (RKE)
System Operation on page 2-4 .
Lamp Messages TURN SIGNAL ON This message displays and a chime
sounds if a turn signal is left on for
1.2 km (0.75 mi). Move the turn
signal lever to the off position. Object Detection System
Messages FORWARD COLLISION
ALERT OFF This message displays when the
Forward Collision Alert has been
turned off.
FRONT CAMERA BLOCKED
CLEAN WINDSHIELD This message displays when the
camera is blocked. Cleaning the
outside of the windshield behind the
rearview mirror may correct the
issue. The Lane Departure Warning
(LDW) system and Forward
Collision Alert (FCA) will not
operate.
LANE DEPARTURE WARNING
UNAVAILABLE
This message displays when
attempting to activate the Lane
Departure Warning (LDW) system 

Black plate (1,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
Vehicle Care 10-1
Vehicle Care General Information General Information . . . . . . . . . . 10-2
California Proposition
65 Warning . . . . . . . . . . . . . . . . . 10-2
California Perchlorate
Materials Requirements . . . . 10-3
Accessories and
Modifications . . . . . . . . . . . . . . . 10-3
Vehicle Checks Doing Your Own
Service Work . . . . . . . . . . . . . . . 10-3
Hood . . . . . . . . . . . . . . . . . . . . . . . . 10-4
Engine Compartment
Overview . . . . . . . . . . . . . . . . . . . 10-5
Engine Oil . . . . . . . . . . . . . . . . . . . 10-8
Engine Oil Life System . . . . . 10-11
Automatic Transmission
Fluid (6 Speed
Transmission) . . . . . . . . . . . . . 10-12
Automatic Transmission
Fluid (8 Speed
Transmission) . . . . . . . . . . . . . 10-15
Engine Air Cleaner/Filter . . . . 10-15
Cooling System . . . . . . . . . . . . 10-17
Engine Coolant . . . . . . . . . . . . . 10-18 Engine Overheating . . . . . . . . 10-21
Overheated Engine
Protection
Operating Mode . . . . . . . . . . . 10-23
Engine Fan . . . . . . . . . . . . . . . . . 10-24
Power Steering Fluid (1500
Series) . . . . . . . . . . . . . . . . . . . . 10-24
Power Steering Fluid (2500/
3500 Series) . . . . . . . . . . . . . . 10-24
Washer Fluid . . . . . . . . . . . . . . . 10-25
Brakes . . . . . . . . . . . . . . . . . . . . . 10-26
Brake Fluid . . . . . . . . . . . . . . . . . 10-27
Battery . . . . . . . . . . . . . . . . . . . . . 10-29
Four-Wheel Drive . . . . . . . . . . . 10-29
Front Axle . . . . . . . . . . . . . . . . . . 10-30
Rear Axle . . . . . . . . . . . . . . . . . . 10-31
Noise Control System . . . . . . 10-32
Starter Switch Check . . . . . . . 10-33
Automatic Transmission Shift
Lock Control Function
Check . . . . . . . . . . . . . . . . . . . . . 10-34
Ignition Transmission Lock
Check . . . . . . . . . . . . . . . . . . . . . 10-34
Park Brake and P (Park)
Mechanism Check . . . . . . . . 10-34
Wiper Blade
Replacement . . . . . . . . . . . . . . 10-35
Glass Replacement . . . . . . . . 10-35 Headlamp Aiming Headlamp Aiming . . . . . . . . . . 10-36
Bulb Replacement Bulb Replacement . . . . . . . . . . 10-36
Halogen Bulbs . . . . . . . . . . . . . . 10-36
LED Lighting . . . . . . . . . . . . . . . 10-36
Headlamps, Front Turn
Signal, Sidemarker, and
Parking Lamps . . . . . . . . . . . . 10-36
Fog Lamps . . . . . . . . . . . . . . . . . 10-37
Taillamps, Turn Signal,
Stoplamps, and Back-Up
Lamps . . . . . . . . . . . . . . . . . . . . 10-37
Center High-Mounted
Stoplamp (CHMSL) and
Cargo Lamp . . . . . . . . . . . . . . 10-39
Replacement Bulbs . . . . . . . . . 10-40
Electrical System Electrical System
Overload . . . . . . . . . . . . . . . . . . 10-40
Fuses . . . . . . . . . . . . . . . . . . . . . . 10-41
Engine Compartment Fuse
Block . . . . . . . . . . . . . . . . . . . . . 10-41
Instrument Panel Fuse
Block (Left) . . . . . . . . . . . . . . . 10-45
Instrument Panel Fuse Block
(Right) . . . . . . . . . . . . . . . . . . . . 10-48 

Black plate (29,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
Vehicle Care 10-29Caution (Continued) be replaced. Do not let
someone put in the wrong
kind of fluid. .
If brake fluid is spilled on the
vehicle's painted surfaces,
the paint finish can be
damaged. Be careful not to
spill brake fluid on the
vehicle. If you do, wash it off
immediately.
Battery Refer to the replacement number
shown on the original battery label
when a new battery is needed. See
Engine Compartment Overview on
page 10-5 for battery location. { WarningBattery posts, terminals, and
related accessories contain lead
and lead compounds, chemicals
known to the State of California to
cause cancer and reproductive
harm. Wash hands after handling.
Vehicle Storage
{ WarningBatteries have acid that can burn
you and gas that can explode.
You can be badly hurt if you are
not careful. See Jump Starting on
page 10-87 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.
Four-Wheel Drive Transfer Case When to Check Lubricant
Refer to Maintenance Schedule on
page 11-3 to determine when to
check the lubricant.
1. Fill Plug
2. Drain Plug 

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 (6,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
13-6 Customer Information .
Model, year, color, and license
plate number of the vehicle. .
Odometer reading, Vehicle
Identification Number (VIN), and
delivery date of the vehicle. .
Description of the problem.
Coverage Services are provided up to 5 years/
160 000 km (100,000 mi), whichever
comes first.
In the U.S., anyone driving the
vehicle is covered. In Canada, a
person driving the vehicle without
permission from the owner is not
covered.
Roadside Assistance is not a part of
the New Vehicle Limited Warranty.
General Motors North America and
GMC reserve the right to make any
changes or discontinue the
Roadside Assistance program at
any time without notification.
General Motors North America and
GMC reserve the right to limit
services or payment to an owner or driver if they decide the claims are
made too often, or the same type of
claim is made many times.
Services Provided .
Emergency Fuel Delivery:
Delivery of enough fuel for the
vehicle to get to the nearest
service station. .
Lock-Out Service: Service to
unlock the vehicle if you are
locked out. A remote unlock may
be available if you have
OnStar ®
. For security reasons,
the driver must present
identification before this service
is given. .
Emergency Tow from a Public
Road or Highway: Tow to the
nearest GMC dealer for warranty
service, or if the vehicle was in a
crash and cannot be driven.
Assistance is not given when the
vehicle is stuck in the sand,
mud, or snow. .
Flat Tire Change: Service to
change a flat tire with the spare
tire. The spare tire, if equipped,
must be in good condition and
properly inflated. It is the owner's
responsibility for the repair or
replacement of the tire if it is not
covered by the warranty. .
Battery Jump Start: Service to
jump start a dead battery. .
Trip Interruption Benefits and
Assistance: If your trip is
interrupted due to a warranty
failure, incidental expenses may
be reimbursed during the
5 years/(160 000 km) 100,000 mi
Powertrain warranty period.
Items considered are hotel,
meals, and rental car.
Services Not Included in
Roadside Assistance .
Impound towing caused by
violation of any laws. .
Legal fines. 

Black plate (2,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
i-2 INDEX
BBattery . . . . . . . . . . . . . . . . . . . . . . . 10-29
Jump Starting . . . . . . . . . . . . . . . 10-87
Load Management . . . . . . . . . . . . . 6-8
Power Protection . . . . . . . . . . . . . . 6-9
Voltage and Charging
Messages . . . . . . . . . . . . . . . . . . . 5-31
Blade Replacement, Wiper . . . 10-35
Blind Spot Mirrors . . . . . . . . . . . . . 2-17
Brake
Pedal and Adjustable
Throttle . . . . . . . . . . . . . . . . . . . . . . 9-23
System Warning Light . . . . . . . . 5-21
Brakes . . . . . . . . . . . . . . . . . . . . . . . . 10-26
Antilock . . . . . . . . . . . . . . . . . . . . . . . 9-46
Assist . . . . . . . . . . . . . . . . . . . . . . . . . 9-48
Fluid . . . . . . . . . . . . . . . . . . . . . . . . 10-27
Parking . . . . . . . . . . . . . . . . . . . . . . . 9-47
System Messages . . . . . . . . . . . . 5-32
Braking . . . . . . . . . . . . . . . . . . . . . . . . . 9-3
Break-In, New Vehicle . . . . . . . . . 9-23 Bulb Replacement . . . . . . . . . . . . 10-40
Center High-Mounted
Stoplamp (CHMSL) and
Cargo Lamp . . . . . . . . . . . . . . . 10-39
Halogen Bulbs . . . . . . . . . . . . . . 10-36
Headlamp Aiming . . . . . . . . . . . 10-36
Headlamps . . . . . . . . . . . . . . . . . 10-36
Headlamps, Front Turn
Signal, Sidemarker, and
Parking Lamps . . . . . . . . . . . . 10-36
Taillamps, Turn Signal,
Stoplamps, and
Back-up Lamps . . . . . . . . . . . 10-37
Buying New Tires . . . . . . . . . . . . . 10-69
C Calibration . . . . . . . . . . . . . . . . . . . . . . 5-4
California
Fuel Requirements . . . . . . . . . . . 9-64
Perchlorate Materials
Requirements . . . . . . . . . . . . . . . 10-3
Warning . . . . . . . . . . . . . . . . . . . . . . 10-2
Canadian Vehicle Owners . . . . . . . . iii
Capacities and
Specifications . . . . . . . . . . . . . . . . 12-2 Carbon Monoxide
Engine Exhaust . . . . . . . . . . . . . . . 9-32
Tailgate . . . . . . . . . . . . . . . . . . . . . . . 2-10
Winter Driving . . . . . . . . . . . . . . . . 9-12
Cargo
Tie-Downs . . . . . . . . . . . . . . . . . . . . . 4-3
Cargo Lamp . . . . . . . . . . . . . . . . . . . . 6-6
Cautions, Danger, and
Warnings . . . . . . . . . . . . . . . . . . . . . . . . iv
Center Console Storage . . . . . . . . 4-2
Center High-Mounted
Stoplamp (CHMSL) and
Cargo Lamp . . . . . . . . . . . . . . . . . 10-39
Chains, Tire . . . . . . . . . . . . . . . . . . 10-74
Charging System Light . . . . . . . . 5-18
Check
Engine Light . . . . . . . . . . . . . . . . . . 5-18
Ignition
Transmission Lock . . . . . . . . 10-34