2015 GMC SIERRA DENALI automatic transmission

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 (7,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
Service and Maintenance 11-7Maintenance Schedule
Additional Required
Services - Severe
12 000 km/7,500 mi
24 000 km/15,000 mi
36 000 km/22,500 mi
48 000 km/30,000 mi
60 000 km/37,500 mi
72 000 km/45,000 mi
84 000 km/52,500 mi
96 000 km/60,000 mi
108 000 km/67,500 mi
120 000 km/75,000 mi
132 000 km/82,500 mi
144 000 km/90,000 mi
156 000 km/97,500 mi
168 000 km/105,000 mi
180 000 km/112,500 mi
192 000 km/120,000 mi
204 000 km/127,500 mi
216 000 km/135,000 mi
228 000 km/142,500 mi
240 000 km/150,000 miRotate tires and perform Required Services.
Check engine oil level and oil life percentage.
Change engine oil and filter, if needed.
@ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @Replace passenger compartment air filter. (1)
@ @ @ @ @ @Inspect evaporative control system. (2)
@ @ @Replace engine air cleaner filter. (3)
@ @ @Replace spark plugs. Inspect spark plug wires.
@Change automatic transmission fluid and filter.
@ @ @Change transfer case fluid, if equipped with
4WD. (4)
@ @ @Extreme Service: Change transfer case fluid,
if equipped with 4WD. (4, 5)
@ @ @ @ @ @Drain and fill engine cooling system. (6)
@Visually inspect accessory drive belts. (7)
@Replace brake fluid. (8)
@ @ @

Black plate (12,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
11-12 Service and Maintenance
Recommended Fluids, Lubricants, and Parts Recommended Fluids and Lubricants This maintenance section applies to vehicles with a gasoline engine. If the vehicle has a diesel engine and/or an
Allison Transmission, see the maintenance schedule section in the Duramax diesel supplement.
Fluids and lubricants identified below by name, part number, or specification can be obtained from your dealer.
Usage Fluid/Lubricant
Engine Oil Use only engine oil licensed to the dexos1 ®
specification of the proper SAE
viscosity grade. ACDelco dexos1 Synthetic Blend is recommended. See
Engine Oil on page 10-8 .
Engine Coolant 50/50 mixture of clean, drinkable water and use only DEX-COOL ®
coolant.
See Engine Coolant on page 10-18 .
Hydraulic Brake System DOT 3 Hydraulic Brake Fluid (GM Part No. 19299818, in
Canada 19299819).
Windshield Washer Automotive windshield washer fluid that meets regional freeze protection
requirements.
Hydraulic Power Steering System
(HD Only) GM Power Steering Fluid (GM Part No. 89021185, in Canada 89021186).
Automatic Transmission (All except
6.2L with 8-Speed transmission) DEXRON ®
-VI Automatic Transmission Fluid.

Black plate (13,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
Service and Maintenance 11-13Usage Fluid/Lubricant
Automatic Transmission (6.2L with
8-Speed transmission) DEXRON ®
-HP Automatic Transmission Fluid (GM Part No. 19300536, in
Canada 19300537).
Transfer Case (Four-Wheel Drive) DEXRON ®
-VI Automatic Transmission Fluid.
Floor Shift Linkage Lubriplate Lubricant Aerosol (GM Part No. 89021668, in Canada 89021674)
or lubricant meeting requirements of NLGI #2 Category LB or GC-LB.
Chassis Lubrication Chassis Lubricant (GM Part No. 12377985, in Canada 88901242) or
lubricant meeting requirements of NLGI #2, Category LB or GC-LB.
Front Axle (1500 Series) –
Four-Wheel Drive SAE 80W-90 Axle Lubricant (GM Part No. 89021671, in
Canada 89021672).
Rear Axle (1500) SAE 75W-85 Synthetic Axle Lubricant (GM Part No. 19300457, in
Canada 19300458).
Front and Rear Axle (2500/3500) SAE 75W-90 Synthetic Axle Lubricant (GM Part No. 88900401, in
Canada 89021678).
Front Axle Driveshaft Splines (All
1500/2500/3500 Series) and Rear
Axle Driveshaft Splines (All 1500
Series with Automatic Transmission) Spline Lubricant, Special Lubricant (GM Part No. 19257121, in
Canada 19257122).

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 (5,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
INDEX i-5FlexFuel
E85 . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-65
Floor Console Storage . . . . . . . . . . 4-3
Floor Mats . . . . . . . . . . . . . . . . . . .10-105
Fluid
Automatic
Transmission . . . . . . . 10-12, 10-15
Brakes . . . . . . . . . . . . . . . . . . . . . . 10-27
Four-Wheel Drive
Transfer Case . . . . . . . . . . . . . . . 9-40
Power Steering . . . . . . . . . . . . . 10-24
Washer . . . . . . . . . . . . . . . . . . . . . 10-25
Fog Lamps . . . . . . . . . . . . . . . . . . . . . 6-5
Bulb Replacement . . . . . . . . . . 10-37
Folding Mirrors . . . . . . . . . . . . . . . . 2-16
Forward Collision Alert
(FCA) System . . . . . . . . . . . . . . . . 9-59
Four-Wheel Drive . . . . . . . 9-40, 10-29
Four-Wheel-Drive Light . . . . . . . . 5-22
Frequency Statement
Radio . . . . . . . . . . . . . . . . . . . . . . . 13-12
Front Axle . . . . . . . . . . . . . . . . . . . . 10-30 Front Fog Lamp
Light . . . . . . . . . . . . . . . . . . . . . . . . . . 5-26
Front Seats
Heated and Cooled . . . . . . . . . . . . 3-7
Fuel . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-63
Additives . . . . . . . . . . . . . . . . . . . . . 9-64
Economy Driving . . . . . . . . . . . . . 1-21
Filling a Portable Fuel
Container . . . . . . . . . . . . . . . . . . . 9-67
Filling the Tank . . . . . . . . . . . . . . . 9-66
Foreign Countries . . . . . . . . . . . . 9-64
Gauge . . . . . . . . . . . . . . . . . . . . . . . . 5-12
Low Fuel Warning Light . . . . . . . 5-25
Management, Active . . . . . . . . . . 9-32
Requirements, California . . . . . 9-64
System Messages . . . . . . . . . . . . 5-35
Full-Size Spare Tire . . . . . . . . . . 10-86
Fuses . . . . . . . . . . . . . . . . . . . . . . . . 10-41
Engine Compartment
Fuse Block . . . . . . . . . . . . . . . . 10-41
Instrument Panel
Fuse Block . . . . . . . . . 10-45, 10-48 G Garage Door Opener . . . . . . . . . . 5-49
Programming . . . . . . . . . . . . . . . . . 5-49
Gauges
Engine Coolant
Temperature . . . . . . . . . . . . . . . . 5-13
Engine Oil Pressure . . . . . . . . . . 5-12
Fuel . . . . . . . . . . . . . . . . . . . . . . . . . . 5-12
Odometer . . . . . . . . . . . . . . . . . . . . . 5-11
Speedometer . . . . . . . . . . . . . . . . . 5-11
Tachometer . . . . . . . . . . . . . . . . . . . 5-11
Transmission Temperature . . . . 5-14
Trip Odometer . . . . . . . . . . . . . . . . 5-11
Voltmeter . . . . . . . . . . . . . . . . . . . . . 5-15
Warning Lights and
Indicators . . . . . . . . . . . . . . . . . . . . 5-8
General Information
Service and Maintenance . . . . . 11-1
Towing . . . . . . . . . . . . . . . . . . . . . . . . 9-68
Vehicle Care . . . . . . . . . . . . . . . . . . 10-2
Glass Replacement . . . . . . . . . . . 10-35
Glove Box . . . . . . . . . . . . . . . . . . . . . . 4-1
GM Mobility Reimbursement
Program . . . . . . . . . . . . . . . . . . . . . . 13-5

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