check engine GMC SIERRA DENALI 2015 Repair Manual

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 (3,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
Technical Data 12-3Application Capacities
Metric English
Fuel Tank
1500 Series 98.4 L 26.0 gal
2500 Series and 3500 Series Standard Box 136.3 L 36.0 gal
3500 Series Long Box 136.3 L 36.0 gal
Transfer Case Fluid 1.5 L 1.6 qt
Wheel Nut Torque 190 Y 140 lb ft
All capacities are approximate. When adding, be sure to fill to the approximate level, as recommended in this
manual. Recheck fluid level after filling.
Engine SpecificationsEngine VIN Code Spark Plug Gap
5.3L V8 (L83) C 0.95 – 1.10 mm (0.037 –
0.043 in)
6.0L V8 (L96) G 0.95 – 1.10 mm (0.037 –
0.043 in)
6.2L V8 (L86) J 0.95 – 1.10 mm (0.037 –
0.043 in)

Black plate (6,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
14-6 OnStar
Vehicle Diagnostics OnStar Vehicle Diagnostics can
perform a vehicle check every
month. It will check the engine,
transmission, antilock brakes, and
other major vehicle systems. It also
checks the tire pressures, if the
vehicle is equipped with the Tire
Pressure Monitoring System. If an
On-Demand Diagnostics check is
needed, press
Q , and an Advisor
can run a check.
OnStar Additional
Information Transferring Service Press
Q to request account transfer
eligibility information. The Advisor
can assist in canceling or removing
account information.
Selling/Transferring the
Vehicle Call 1-888-4-ONSTAR immediately
to terminate your OnStar services if
the vehicle is disposed of, sold,
transferred, or if the lease ends.
Reactivation for Subsequent
Owners
Press
Q and follow the prompts to
speak to an Advisor as soon as
possible. The Advisor will update
vehicle records and explain the
OnStar service options available. How OnStar Service Works Automatic Crash Response,
Emergency Services, Crisis Assist,
Stolen Vehicle Assistance, Vehicle
Diagnostics, Remote Door Unlock,
Roadside Assistance, Turn-by-Turn
Navigation, and Hands-Free Calling
are available on most vehicles. Not
all OnStar services are available
everywhere or on all vehicles. For
more information, a full description
of OnStar services, system
limitations, and OnStar terms and
conditions: .
Call 1-888-4-ONSTAR
(1-888-466-7827). .
See www.onstar.com (U.S.). .
See www.onstar.ca (Canada). .
Call TTY 1-877-248-2080. .
Press
Q to speak with an
Advisor.
OnStar services cannot work unless
the vehicle is in a place where
OnStar has an agreement with a
wireless service provider for service

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

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

Black plate (4,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
i-4 INDEX Driving (cont'd)
Drunk . . . . . . . . . . . . . . . . . . . . . . . . . . 9-3
For Better Fuel Economy . . . . . 1-21
Hill and Mountain Roads . . . . . . 9-11
If the Vehicle is Stuck . . . . . . . . . 9-14
Loss of Control . . . . . . . . . . . . . . . . 9-5
Off-Road . . . . . . . . . . . . . . . . . . . . . . 9-6
Off-Road Recovery . . . . . . . . . . . . 9-5
Vehicle Load Limits . . . . . . . . . . . 9-15
Wet Roads . . . . . . . . . . . . . . . . . . . 9-11
Winter . . . . . . . . . . . . . . . . . . . . . . . . 9-12
Dual Automatic Climate
Control System . . . . . . . . . . . . . . . . 8-1
Dual Tire
Rotation . . . . . . . . . . . . . . . . . . . . 10-67
EE85 or FlexFuel . . . . . . . . . . . . . . . 9-65
Electrical Equipment,
Add-On . . . . . . . . . . . . . . . . . . . . . . 9-88
Electrical System
Engine Compartment
Fuse Block . . . . . . . . . . . . . . . . 10-41
Fuses . . . . . . . . . . . . . . . . . . . . . . 10-41 Electrical System (cont'd)
Instrument Panel
Fuse Block . . . . . . . . . 10-45, 10-48
Overload . . . . . . . . . . . . . . . . . . . 10-40
Emergency
OnStar ®
. . . . . . . . . . . . . . . . . . . . . . 14-2
Engine
Air Cleaner/Filter . . . . . . . . . . . 10-15
Check and Service Engine
Soon Light . . . . . . . . . . . . . . . . . . 5-18
Compartment Overview . . . . . . . 10-5
Coolant . . . . . . . . . . . . . . . . . . . . . 10-18
Coolant Temperature
Gauge . . . . . . . . . . . . . . . . . . . . . . 5-13
Coolant Temperature
Warning Light . . . . . . . . . . . . . . . 5-24
Cooling System . . . . . . . . . . . . . 10-17
Cooling System Messages . . . 5-33
Drive Belt Routing . . . . . . . . . . . . 12-4
Exhaust . . . . . . . . . . . . . . . . . . . . . . 9-32
Fan . . . . . . . . . . . . . . . . . . . . . . . . . 10-24
Heater . . . . . . . . . . . . . . . . . . . . . . . . 9-28
Oil Life System . . . . . . . . . . . . . .10-11
Oil Messages . . . . . . . . . . . . . . . . . 5-34
Oil Pressure Gauge . . . . . . . . . . 5-12
Overheated Protection
Operating Mode . . . . . . . . . . . 10-23 Engine (cont'd)
Overheating . . . . . . . . . . . . . . . . 10-21
Power Messages . . . . . . . . . . . . . 5-34
Pressure Light . . . . . . . . . . . . . . . . 5-25
Running While Parked . . . . . . . . 9-33
Starting . . . . . . . . . . . . . . . . . . . . . . . 9-26
Entry Lighting . . . . . . . . . . . . . . . . . . . 6-8
Equipment, Towing . . . . . . . . . . . . 9-78
Event Data Recorders . . . . . . . . 13-14
Exit Lighting . . . . . . . . . . . . . . . . . . . . 6-8
Extender, Safety Belt . . . . . . . . . . 3-15
Exterior Lamp Controls . . . . . . . . . 6-1
Exterior Lamps Off Reminder . . . 6-2
F Fan
Engine . . . . . . . . . . . . . . . . . . . . . . 10-24
Fast Idle System . . . . . . . . . . . . . . . 9-27
Features
Memory . . . . . . . . . . . . . . . . . . . . . . . . 1-8
Filter,
Engine Air Cleaner . . . . . . . . . 10-15
Flash-to-Pass . . . . . . . . . . . . . . . . . . . 6-2
Flashers, Hazard Warning . . . . . . 6-4
Flat Tire . . . . . . . . . . . . . . . . . . . . . . 10-74
Changing . . . . . . . . . . . . . . . . . . . 10-76

Black plate (6,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
i-6 INDEX
HHalogen Bulbs . . . . . . . . . . . . . . . . 10-36
Hazard Warning Flashers . . . . . . . 6-4
Head Restraints . . . . . . . . . . . . . . . . 3-2
Headlamps
Aiming . . . . . . . . . . . . . . . . . . . . . . 10-36
Automatic . . . . . . . . . . . . . . . . . . . . . . 6-3
Bulb Replacement . . . . . . . . . . 10-36
Daytime Running
Lamps (DRL) . . . . . . . . . . . . . . . . . 6-3
Flash-to-Pass . . . . . . . . . . . . . . . . . . 6-2
Headlamps, Front Turn
Signal, Sidemarker, and
Parking Lamps . . . . . . . . . . . . 10-36
High-Beam On Light . . . . . . . . . . 5-26
High/Low Beam Changer . . . . . . 6-2
Lamps On Reminder . . . . . . . . . 5-26
Heated
Steering Wheel . . . . . . . . . . . . . . . . 5-3
Heated and Cooled Front
Seats . . . . . . . . . . . . . . . . . . . . . . . . . 3-7
Heated Mirrors . . . . . . . . . . . . . . . . . 2-17
Heater
Engine . . . . . . . . . . . . . . . . . . . . . . . . 9-28
High-Beam On Light . . . . . . . . . . . 5-26 High-Speed Operation . . . . . . . . 10-60
Hill and Mountain Roads . . . . . . . 9-11
Hill Descent Control (HDC) . . . . 9-51
Hill Descent Control Light . . . . . . 5-22
Hill Start Assist (HSA) . . . . . . . . . 9-48
Hood . . . . . . . . . . . . . . . . . . . . . . . . . . 10-4
Horn . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-3
How to Wear Safety Belts
Properly . . . . . . . . . . . . . . . . . . . . . . 3-11
I Idle System
Fast . . . . . . . . . . . . . . . . . . . . . . . . . . 9-27
Ignition Positions . . . . . . . . . . . . . . 9-24
Ignition Transmission Lock
Check . . . . . . . . . . . . . . . . . . . . . . . 10-34
Immobilizer . . . . . . . . . . . . . . . . . . . . 2-12
Indicator
Vehicle Ahead . . . . . . . . . . . . . . . . 5-23
Infants and Young Children,
Restraints . . . . . . . . . . . . . . . . . . . . 3-32
Infotainment . . . . . . . . . . . . . . . . . . . . 7-1
Infotainment System . . . . . . . . . . 13-15
Instrument Cluster . . . . . . . . . . . . . . 5-9
Instrument Panel
Storage Area . . . . . . . . . . . . . . . . . . 4-1 Interior Rearview Mirrors . . . . . . . 2-19
Introduction . . . . . . . . . . . . . . . . . . . . . . . iii
J Jump Starting . . . . . . . . . . . . . . . . . 10-87
K Key and Lock Messages . . . . . . . 5-35
Keyless Entry
Remote (RKE) System . . . . . . . . 2-4
Keys . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-1
L Labeling, Tire Sidewall . . . . . . . . 10-52
Lamps
Auxiliary Roof
Mounted Lamp . . . . . . . . . . . . . . . 6-5
Cargo . . . . . . . . . . . . . . . . . . . . . . . . . . 6-6
Daytime Running (DRL) . . . . . . . 6-3
Dome . . . . . . . . . . . . . . . . . . . . . . . . . . 6-7
Exterior Controls . . . . . . . . . . . . . . . 6-1
Exterior Lamps Off
Reminder . . . . . . . . . . . . . . . . . . . . 6-2
Fog . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-5
Malfunction Indicator . . . . . . . . . 5-18

Black plate (9,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
INDEX i-9OnStar ®
Security . . . . . . . . . . . . . . 14-3
OnStar ®
Vehicle
Diagnostics . . . . . . . . . . . . . . . . . . 14-6
Operating Mode
Overheated Engine
Protection . . . . . . . . . . . . . . . . . 10-23
Ordering
Service Publications . . . . . . . . .13-11
Outlets
Power . . . . . . . . . . . . . . . . . . . . . . . . . 5-5
Overheated Engine
Protection
Operating Mode . . . . . . . . . . . . . 10-23
Overheating, Engine . . . . . . . . . . 10-21
PPark
Shifting Into . . . . . . . . . . . . . . . . . . . 9-30
Shifting Out of . . . . . . . . . . . . . . . . 9-31
Parking
Brake . . . . . . . . . . . . . . . . . . . . . . . . . 9-47
Brake and P (Park)
Mechanism Check . . . . . . . . 10-34
Over Things That Burn . . . . . . . 9-32 Parking or Backing
Assistance Systems . . . . . . . . . . 9-56
Passenger Airbag Status
Indicator . . . . . . . . . . . . . . . . . . . . . 5-17
Passenger Compartment Air
Filter . . . . . . . . . . . . . . . . . . . . . . . . . . 8-5
Passenger Sensing System . . . 3-24
Perchlorate Materials
Requirements, California . . . . . 10-3
Personalization
Vehicle . . . . . . . . . . . . . . . . . . . . . . . 5-42
Pickup Conversion to
Chassis Cab . . . . . . . . . . . . . . . . . 9-92
Power
Door Locks . . . . . . . . . . . . . . . . . . . . 2-9
Mirrors . . . . . . . . . . . . . . . . . . . . . . . . 2-14
Outlets . . . . . . . . . . . . . . . . . . . . . . . . 5-5
Protection, Battery . . . . . . . . . . . . . 6-9
Retained Accessory (RAP) . . . 9-29
Seat Adjustment . . . . . . . . . . . . . . . 3-3
Steering Fluid . . . . . . . . . . . . . . . 10-24
Windows . . . . . . . . . . . . . . . . . . . . . 2-19
Pregnancy, Using Safety
Belts . . . . . . . . . . . . . . . . . . . . . . . . . 3-15
Privacy
Vehicle Data Recording . . . . . 13-14 Program
Courtesy Transportation . . . . . . 13-8
Proposition 65 Warning,
California . . . . . . . . . . . . . . . . . . . . . 10-2
R Radio Frequency
Identification (RFID) . . . . . . . . . 13-12
Radio Frequency
Statement . . . . . . . . . . . . . . . . . . . 13-12
Reading Lamps . . . . . . . . . . . . . . . . . 6-7
Rear Axle . . . . . . . . . . . . . . . . . . . . . 10-31
Locking . . . . . . . . . . . . . . . . . . . . . . . 9-52
Rear Seats . . . . . . . . . . . . . . . . . . . . . 3-9
Rear Windows . . . . . . . . . . . . . . . . . 2-22
Rearview Mirrors
Automatic Dimming . . . . . . . . . . . 2-19
Reclining Seatbacks . . . . . . . . . . . . 3-4
Recommended Fluids and
Lubricants . . . . . . . . . . . . . . . . . . . 11-12
Records
Maintenance . . . . . . . . . . . . . . . . .11-16
Recreational Vehicle
Towing . . . . . . . . . . . . . . . . . . . . . . 10-91
Reimbursement Program,
GM Mobility . . . . . . . . . . . . . . . . . . 13-5

Black plate (10,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
i-10 INDEX Remote Keyless Entry (RKE)
System . . . . . . . . . . . . . . . . . . . . . . . . 2-4
Remote Vehicle Start . . . . . . . . . . . 2-7
Replacement
Glass . . . . . . . . . . . . . . . . . . . . . . . 10-35
Replacement Bulbs . . . . . . . . . . . 10-40
Replacement Parts
Airbags . . . . . . . . . . . . . . . . . . . . . . . 3-30
Maintenance . . . . . . . . . . . . . . . . .11-14
Replacing Airbag System . . . . . . 3-30
Replacing LATCH System
Parts after a Crash . . . . . . . . . . . 3-45
Replacing Safety Belt
System Parts after a Crash . . . 3-16
Reporting Safety Defects
Canadian Government . . . . . . 13-13
General Motors . . . . . . . . . . . . . 13-13
U.S. Government . . . . . . . . . . . 13-13
Restraints
Where to Put . . . . . . . . . . . . . . . . . 3-37
Retained Accessory
Power (RAP) . . . . . . . . . . . . . . . . . 9-29
Reverse Tilt Mirrors . . . . . . . . . . . . 2-18
Ride Control Systems
Messages . . . . . . . . . . . . . . . . . . . . 5-36 Roads
Driving, Wet . . . . . . . . . . . . . . . . . . 9-11
Roadside Assistance
Program . . . . . . . . . . . . . . . . . . . . . . 13-5
Roof
Sunroof . . . . . . . . . . . . . . . . . . . . . . . 2-22
Rotation, Tires . . . . . . . . . . . . . . . . 10-65
Routing, Engine Drive Belt . . . . . 12-4
Running the Vehicle While
Parked . . . . . . . . . . . . . . . . . . . . . . . 9-33
S Safety Belts . . . . . . . . . . . . . . . . . . . 3-10
Care . . . . . . . . . . . . . . . . . . . . . . . . . . 3-16
Extender . . . . . . . . . . . . . . . . . . . . . . 3-15
How to Wear Safety Belts
Properly . . . . . . . . . . . . . . . . . . . . . 3-11
Lap-Shoulder Belt . . . . . . . . . . . . 3-12
Messages . . . . . . . . . . . . . . . . . . . . 5-37
Reminders . . . . . . . . . . . . . . . . . . . . 5-15
Replacing after a Crash . . . . . . 3-16
Use During Pregnancy . . . . . . . . 3-15 Safety Defects Reporting
Canadian Government . . . . . . 13-13
General Motors . . . . . . . . . . . . . 13-13
U.S. Government . . . . . . . . . . . 13-13
Safety Locks . . . . . . . . . . . . . . . . . . . . 2-9
Safety System Check . . . . . . . . . . 3-16
Scheduling Appointments . . . . . . 13-7
Seats
Head Restraints . . . . . . . . . . . . . . . 3-2
Lumbar Adjustment, Front . . . . . 3-3
Memory . . . . . . . . . . . . . . . . . . . . . . . . 3-5
Power Adjustment, Front . . . . . . 3-3
Rear . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-9
Reclining Seatbacks . . . . . . . . . . . 3-4
Securing Child
Restraints . . . . . . . . . . . . . . 3-45, 3-47
Security
Light . . . . . . . . . . . . . . . . . . . . . . . . . . 5-26
Messages . . . . . . . . . . . . . . . . . . . . 5-38
OnStar ®
. . . . . . . . . . . . . . . . . . . . . . 14-3
Vehicle . . . . . . . . . . . . . . . . . . . . . . . 2-11
Vehicle Alarm . . . . . . . . . . . . . . . . . 2-11

Black plate (11,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
INDEX i-11Service . . . . . . . . . . . . . . . . . . . . . . . . . 8-6
Accessories and
Modifications . . . . . . . . . . . . . . . . 10-3
Doing Your Own Work . . . . . . . . 10-3
Engine Soon Light . . . . . . . . . . . . 5-18
Maintenance Records . . . . . . .11-16
Maintenance, General
Information . . . . . . . . . . . . . . . . . . 11-1
Parts Identification Label . . . . . 12-1
Publications Ordering
Information . . . . . . . . . . . . . . . . .13-11
Scheduling Appointments . . . . . 13-7
Services
Special Application . . . . . . . . . . . 11-8
Servicing the Airbag . . . . . . . . . . . 3-28
Shift Lock Control Function
Check, Automatic
Transmission . . . . . . . . . . . . . . . . 10-34
Shifting
Into Park . . . . . . . . . . . . . . . . . . . . . . 9-30
Out of Park . . . . . . . . . . . . . . . . . . . 9-31
Signals, Turn and
Lane-Change . . . . . . . . . . . . . . . . . 6-4
Snow Plow . . . . . . . . . . . . . . . . . . . . 9-88
Special Application Services . . . 11-8 Specifications and
Capacities . . . . . . . . . . . . . . . . . . . . 12-2
Speedometer . . . . . . . . . . . . . . . . . . 5-11
StabiliTrak
OFF Light . . . . . . . . . . . . . . . . . . . . . 5-23
Start Assist, Hills . . . . . . . . . . . . . . 9-48
Start Vehicle, Remote . . . . . . . . . . 2-7
Starter Switch Check . . . . . . . . . 10-33
Starting the Engine . . . . . . . . . . . . 9-26
Steering . . . . . . . . . . . . . . . . . . . . . . . . 9-4
Fluid, Power . . . . . . . . . . . . . . . . 10-24
Heated Wheel . . . . . . . . . . . . . . . . . 5-3
Wheel Adjustment . . . . . . . . . . . . . 5-2
Wheel Controls . . . . . . . . . . . . . . . . 5-2
Steering System Messages . . . . 5-38
Stoplamps and Back-up Lamps
Bulb Replacement . . . . . . . . . . 10-37
Storage Areas
Center Console . . . . . . . . . . . . . . . . 4-2
Floor Console . . . . . . . . . . . . . . . . . 4-3
Glove Box . . . . . . . . . . . . . . . . . . . . . 4-1
Instrument Panel . . . . . . . . . . . . . . 4-1
Sunglasses . . . . . . . . . . . . . . . . . . . . 4-2
Storage Compartments . . . . . . . . . 4-1
Stuck Vehicle . . . . . . . . . . . . . . . . . . 9-14
Sun Visors . . . . . . . . . . . . . . . . . . . . . 2-22 Sunglass Storage . . . . . . . . . . . . . . . 4-2
Sunroof . . . . . . . . . . . . . . . . . . . . . . . . 2-22
Symbols . . . . . . . . . . . . . . . . . . . . . . . . . . iv
System
Forward Collision
Alert (FCA) . . . . . . . . . . . . . . . . . . 9-59
Infotainment . . . . . . . . . . . . 7-1, 13-15
Noise Control . . . . . . . . . . . . . . . 10-32
Systems
Driver Assistance . . . . . . . . . . . . . 9-55
T Tachometer . . . . . . . . . . . . . . . . . . . . 5-11
Tailgate . . . . . . . . . . . . . . . . . . . . . . . . 2-10
Taillamps
Bulb Replacement . . . . . . . . . . 10-37
Text Telephone (TTY) Users . . . 13-4
Theft-Deterrent Systems . . . . . . . 2-13
Immobilizer . . . . . . . . . . . . . . . . . . . 2-12
Throttle, Adjustable . . . . . . . . . . . . 9-23
Time . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-4
Tires . . . . . . . . . . . . . . . . . . . . . . . . . . 10-50
All-Season . . . . . . . . . . . . . . . . . . 10-51
All-Terrain . . . . . . . . . . . . . . . . . . 10-52
Buying New Tires . . . . . . . . . . . 10-69
Chains . . . . . . . . . . . . . . . . . . . . . . 10-74