GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 8/27/19
450 Service and Maintenance
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 0435 and
Exterior Care 0429.
Wheel Alignment
Wheel alignment is critical for
ensuring that the tires deliver
optimal wear and performance.
. Signs that the alignment may
need to be adjusted include
pulling, improper vehicle
handling, or unusual tire wear.
. Your dealer has the required
equipment to ensure proper
wheel alignment.
Windshield
For safety, appearance, and the
best viewing, keep the windshield
clean and clear.
. Signs of damage include
scratches, cracks, and chips.
GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 8/27/19
Service and Maintenance 453
UsageFluid/Lubricant
Front Axle (Four-Wheel Drive) and Rear Axle See your dealer.
Hydraulic Brake System (Vehicles with DOT 3 brake fluid) DOT 3 Hydraulic Brake Fluid (GM Part No. 19353126, in
Canada 19353127). See
Brake Fluid0357.
Hydraulic Brake System (Vehicles with DOT 4 brake fluid) DOT 4 Hydraulic Brake Fluid (GM Part No. 19299570, in
Canada 19299571). See
Brake Fluid0357.
Hydraulic Power Steering System (2500/3500 Series Only) GM Power Steering Fluid (GM Part No. 19329450, in Canada 19329451).
Key Lock Cylinders, Hood Hinges, Body Door Hinge Pins, Tailgate
Hinge and Linkage, Fuel Door Hinge, Tailgate Handle Pivot Points, Hinges, Latch Bolt, and Linkage Multi-Purpose Lubricant, Superlube (GM Part No. 12346241, in
Canada 10953474).
Transfer Case (Four-Wheel Drive) DEXRON-VI Automatic Transmission Fluid. Weatherstrip Conditioning Weatherstrip Lubricant. See your dealer.Weatherstrip Squeaks Synthetic Grease with Teflon, Superlube (GM Part No. 12371287).
Windshield Washer Automotive windshield washer fluid that meets regional freeze protection requirements.
GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 8/27/19
460 Technical Data
ApplicationCapacities
Metric English
3500 Series Chassis Cab –Rear Tank 151.4 L 40.0 gal
Transfer Case Fluid (1500 Series Only) 1.5 L 1.6 qt
Transfer Case Fluid (2500 and 3500 Series Only) 2.3 L 2.4 qt
Wheel Nut Torque 190 Y140 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 cooling system capacity values are based on the entire cooling system and its components.
Engine Specifications
Engine VIN CodeSpark Plug Gap
2.7L L4 (L3B) K0.65–0.75 mm (0.026–0.030 in)
4.3L V6 (LV3) H0.95–1.10 mm (0.037–0.043 in)
5.3L V8 (L82) F0.95–1.10 mm (0.037–0.043 in)
5.3L V8 (L84) D0.95–1.10 mm (0.037–0.043 in)
6.2L V8 (L87) L0.95–1.10 mm (0.037–0.043 in)
6.6L V8 (L8T) 70.95–1.10 mm (0.037–0.043 in)
Spark plug gaps are preset by the manufacturer. Re-gapping the spark plug is not recommended and can damage
the spark plug.
GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 8/27/19
Customer Information 465
Customer Assistance for
Text Telephone (TTY)
Users
To assist customers who are deaf,
hard of hearing, or speech-impaired
and who use Text Telephones
(TTYs), GMC has TTY equipment
available at its Customer Assistance
Center. Any TTY user in the U.S.
can communicate with GMC by
dialing: 1-888-889-2438. TTY users
in Canada can dial 1-800-263-3830.
Online Owner Center
Online Owner Experience
(U.S.) my.gmc.com
The GMC online owner experience
allows access to videos, articles,
and vehicle health specific to your
GMC as well as your OnStar
Account information all in one place.
Membership Benefits
E:Download owner ’s manuals
and view vehicle-specific how-to
videos.
G: View maintenance schedules,
alerts, and Vehicle Diagnostic
Information. Schedule service
appointments.
I: View and print dealer-recorded
service records and self-recorded
service records.
D: Select a dealer and view
locations, maps, phone numbers,
and hours.
r: Track your vehicle’s warranty
information.
J: View active recalls by Vehicle
Identification Number (VIN). See
Vehicle Identification Number (VIN)
0 457.
H:Compare and shop for GMC
and OnStar plans and Services.
View GM Card and SiriusXM
information (if equipped).
F: Chat live with online help
representatives.
See my.gmc.com to register your
vehicle.
GMC Owner Centre (Canada)
mygmccanada.ca
Visit the GMC Owner Centre at
mygmccanada.ca (English) or
my.gmccanada.ca (French) to
access similar benefits to the
U.S. site.
GM Mobility
Reimbursement Program
This program is available to
qualified applicants for cost
reimbursement, up to certain limits,
of eligible aftermarket adaptive
equipment required for the vehicle,
such as hand controls or a
wheelchair/scooter lift for the
vehicle.
To learn about the GM Mobility
program, see www.gmmobility.com
or call the GM Mobility Assistance
GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/-
Mexico-13337776) - 2020 - CRC - 8/27/19
Index 491
Extender, Seat Belt . . . . . . . . . . . . . . 70
Exterior Cargo Lamps . . . . . . . . . . 171
Exterior Lamp Controls . . . . . . . . . 165
Exterior Lamps Off Reminder . . . 167
Exterior Lighting BatterySaver . . . . . . . . . . . . . . . . . . . . . . . . . 174
F
FanEngine . . . . . . . . . . . . . . . . . . . . . . . . 353
Filter, Engine Air Cleaner . . . . . . . . . . . 344
Flash-to-Pass . . . . . . . . . . . . . . . . . . . 168
Flashers, Hazard Warning . . . . . . 169
Flat Tire . . . . . . . . . . . . . . . . . . . . . . . . 405 Changing . . . . . . . . . . . . . . . . . . . . . 407
FlexFuel
E85 . . . . . . . . . . . . . . . . . . . . . . . . . . . 282
Floor Console Storage . . . . . . . . . . 114
Floor Mats . . . . . . . . . . . . . . . . . . . . . . 438
Fluid Automatic Transmission . . . . . . 343
Brakes . . . . . . . . . . . . . . . . . . . . . . . . 357
Four-Wheel DriveTransfer Case . . . . . . . . . . . . . . . 227
Power Steering . . . . . . . . . . . . . . . 354
Washer . . . . . . . . . . . . . . . . . . . . . . . 354
Fog Lamps . . . . . . . . . . . . . . . . . . . . . 170 Folding Mirrors . . . . . . . . . . . . . . . . . . 42
Forward Collision Alert
(FCA) System . . . . . . . . . . . . . . . . . 268
Four-Wheel Drive . . . . . . . . . . 227, 361
Four-Wheel-Drive Light . . . . . . . . . 141
Frequency Statement Radio . . . . . . . . . . . . . . . . . . . . . . . . . 472
Front Axle . . . . . . . . . . . . . . . . . . . . . . 361
Front Fog Lamp Light . . . . . . . . . . . . . . . . . . . . . . . . . . 146
Front Pedestrian Braking
(FPB) System . . . . . . . . . . . . . . . . . 272
Front Seats Adjustment . . . . . . . . . . . . . . . . . . . . . 54
Heated and Ventilated . . . . . . . . . . 60
Fuel
Additives . . . . . . . . . . . . . . . . . . . . . 282
Economy, Driving for Better . . . 186
Filling a Portable FuelContainer . . . . . . . . . . . . . . . . . . . 286
Filling the Tank . . . . . . . . . . 283, 285
Foreign Countries . . . . . . . . . . . . 281
Gauge . . . . . . . . . . . . . . . . . . . . . . . . 131
Low Fuel Warning Light . . . . . . . 145
Management, Active . . . . . . . . . . 219
Prohibited Fuels . . . . . . . . . . . . . . 281
Recommended . . . . . . . . . . 280, 281
Top Tier . . . . . . . . . . . . . . . . . . . . . . 280 Full-Size Spare Tire . . . . . . . . . . . . 418
Fuses
Engine Compartment FuseBlock . . . . . . . . . . . . . . . . . . . . . . . . 371
Fuses and Circuit Breakers . . . 370
Instrument Panel Fuse Block . . . . . . . . . . . . . . . . . . . 374, 376G
Garage Door Opener . . . . . . . . . . . 161
Programming . . . . . . . . . . . . . . . . . 161
Gas Strut(s) . . . . . . . . . . . . . . . . . . . . 365
Gauges
Engine CoolantTemperature . . . . . . . . . . . . . . . . 133
Engine Oil Pressure . . . . . . . . . . 132
Fuel . . . . . . . . . . . . . . . . . . . . . . . . . . 131
Odometer . . . . . . . . . . . . . . . . . . . . . 131
Speedometer . . . . . . . . . . . . . . . . . 130
Tachometer . . . . . . . . . . . . . . . . . . . 131
Trip Odometer . . . . . . . . . . . . . . . . 131
Voltmeter . . . . . . . . . . . . . . . . . . . . . 134
Warning Lights and Indicators . . . . . . . . . . . . . . . . . . . 125
General Information Service and Maintenance . . . . . 439
Towing . . . . . . . . . . . . . . . . . . . . . . . . 287
Vehicle Care . . . . . . . . . . . . . . . . . . 328
GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/-
Mexico-13337776) - 2020 - CRC - 8/27/19
492 Index
Glove Box . . . . . . . . . . . . . . . . . . . . . . 112
GM Mobility ReimbursementProgram . . . . . . . . . . . . . . . . . . . . . . . 465
H
Halogen Bulbs . . . . . . . . . . . . . . . . . . 367
Hazard Warning Flashers . . . . . . . 169
Head Restraints . . . . . . . . . . . . . . . . . 53
Head-up Display . . . . . . . . . . . . . . . . 152
HeadlampsAiming . . . . . . . . . . . . . . . . . . . . . . . . 366
Automatic . . . . . . . . . . . . . . . . . . . . . 168
Bulb Replacement . . . . . . . . . . . . 367
Daytime RunningLamps (DRL) . . . . . . . . . . . . . . . . 168
Flash-to-Pass . . . . . . . . . . . . . . . . . 168
Headlamps, Front Turn Signal, Sidemarker, and
Parking Lamps . . . . . . . . . . . . . . 367
High-Beam On Light . . . . . . . . . . 146
High/Low Beam Changer . . . . . 167
Lamps On Reminder . . . . . . . . . 146
Heated Rear Seats . . . . . . . . . . . . . . . . . . . . . 63
Steering Wheel . . . . . . . . . . . . . . . .119
Heated and Ventilated Front
Seats . . . . . . . . . . . . . . . . . . . . . . . . . . 60
Heated Mirrors . . . . . . . . . . . . . . . . . . . 43 Heater
Engine . . . . . . . . . . . . . . . . . . . . . . . . 215
Heating . . . . . . . . . . . . . . . . . . . . 177, 179
High-Beam On Light . . . . . . . . . . . . 146
High-Speed Operation . . . . . . . . . . 389
Hill and Mountain Roads . . . . . . . . 197
Hill Descent Control (HDC) . . . . . 237
Hill Descent Control Light . . . . . . . 141
Hill Start Assist (HSA) . . . . . . . . . . 235
Hood . . . . . . . . . . . . . . . . . . . . . . . . . . . 330
Horn . . . . . . . . . . . . . . . . . . . . . . . . . . . . 119
How to Wear Seat Belts Properly . . . . . . . . . . . . . . . . . . . . . . . . 65
HVAC . . . . . . . . . . . . . . . . . . . . . . 177, 179
I
Ignition Positions . . . . . . . . . . 208, 210
Ignition Transmission Lock Check . . . . . . . . . . . . . . . . . . . . . . . . . 363
Immobilizer . . . . . . . . . . . . . . . . . . . . . . 37
Indicator Pedestrian Ahead . . . . . . . . . . . . 142
Vehicle Ahead . . . . . . . . . . . . . . . . 142
Infants and Young Children, Restraints . . . . . . . . . . . . . . . . . . . . . . 86
Information
Publication Ordering . . . . . . . . . . 471
Infotainment . . . . . . . . . . . . . . . . . . . . 176 Infotainment System . . . . . . . . . . . . 475
Instrument Cluster . . . . . . . . . . . . . . 126
Instrument Panel Overview . . . . . . . 5
Interior Rearview Mirrors . . . . . . . . . 44
Introduction . . . . . . . . . . . . . . . . . . . . . . . 2
J
Jump Starting - North
America . . . . . . . . . . . . . . . . . . . . . . . 419
K
Keyless EntryRemote (RKE) System . . . . . 13, 16
Keys . . . . . . . . . . . . . . . . . . . . . . . . . . .9, 12
L
Labeling, Tire Sidewall . . . . . . . . . . 381
Lamps Daytime Running (DRL) . . . . . . 168
Dome . . . . . . . . . . . . . . . . . . . . . . . . . 172
Exterior Cargo . . . . . . . . . . . . . . . . 171
Exterior Controls . . . . . . . . . . . . . . 165
Exterior Lamps OffReminder . . . . . . . . . . . . . . . . . . . 167
Exterior Lighting Battery Saver . . . . . . . . . . . . . . . . . . . . . . . 174
License Plate . . . . . . . . . . . . . . . . . 369
Malfunction Indicator (Check Engine) . . . . . . . . . . . . . 137
GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/-
Mexico-13337776) - 2020 - CRC - 8/27/19
Index 493
Lamps (cont'd)On Reminder . . . . . . . . . . . . . . . . . 146
Reading . . . . . . . . . . . . . . . . . . . . . . 173
Lane Change Alert (LCA) . . . . . . . 274
Lane Departure
Warning (LDW) . . . . . . . . . . . . . . . . 276
Lane Departure Warning Light . . . . . . . . . . . . . . . . . . . . . . . . . . 141
Lane Keep Assist (LKA) . . . . . . . . 278
Lane Keep Assist Light . . . . . . . . . 142
Lap-Shoulder Belt . . . . . . . . . . . . . . . 67
LATCH System
Replacing Parts after aCrash . . . . . . . . . . . . . . . . . . . . . . . 104
LATCH, Lower Anchors and Tethers for Children . . . . . . . . . . . . 91
LED Lighting . . . . . . . . . . . . . . . . . . . . 367
Lighting Entry . . . . . . . . . . . . . . . . . . . . . . . . . 173
Exit . . . . . . . . . . . . . . . . . . . . . . . . . . . 173
Illumination Control . . . . . . . . . . . 172
LED . . . . . . . . . . . . . . . . . . . . . . . . . . 367
Task . . . . . . . . . . . . . . . . . . . . . . . . . . 171
Lights Airbag Readiness . . . . . . . . . . . . . 135
Antilock Brake System(ABS) Warning . . . . . . . . . . . . . . 140
Brake System Warning . . . . . . . 139 Lights (cont'd)
Charging System . . . . . . . . . . . . . 137
Check Engine (Malfunction
Indicator) . . . . . . . . . . . . . . . . . . . . 137
Cruise Control . . . . . . . . . . . . . . . . 146
Door Ajar . . . . . . . . . . . . . . . . . . . . . 147
Driver Mode Control . . . . . . . . . . 144
Electric Parking Brake . . . . . . . . 140
Electronic Stability Control (ESC), Off . . . . . . . . . . . . . . . . . . . 143
Engine Coolant Temperature Warning . . . . . . . 144
Engine Oil Pressure . . . . . . . . . . 145
Flash-to-Pass . . . . . . . . . . . . . . . . . 168
Four-Wheel-Drive . . . . . . . . . . . . . 141
Front Fog Lamp . . . . . . . . . . . . . . 146
High-Beam On . . . . . . . . . . . . . . . . 146
High/Low Beam Changer . . . . . 167
Hill Descent Control . . . . . . . . . . 141
Lane Departure Warning . . . . . . 141
Lane Keep Assist . . . . . . . . . . . . . 142
Low Fuel Warning . . . . . . . . . . . . 145
Seat Belt Reminders . . . . . . . . . . 135
Security . . . . . . . . . . . . . . . . . . . . . . 146
Service Electric Parking Brake . . . . . . . . . . . . . . . . . . . . . . . 140
Tire Pressure . . . . . . . . . . . . . . . . . 144
Tow/Haul Mode . . . . . . . . . . . . . . . 141 Lights (cont'd)
Traction Off . . . . . . . . . . . . . . . . . . . 142
Limited-Slip Differential . . . . . . . . . 242
Lock Steering Column . . . . . . . . . . . . . . . . 37
Locking Rear Axle . . . . . . . . . . . . . . 242
Locks Automatic Door . . . . . . . . . . . . . . . . . 27
Delayed Locking . . . . . . . . . . . . . . . . 27
Door . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
Lockout Protection . . . . . . . . . . . . . . 28
Power Door . . . . . . . . . . . . . . . . . . . . . 27
Safety . . . . . . . . . . . . . . . . . . . . . . . . . . 28
Loss of Control . . . . . . . . . . . . . . . . . 190
Low Fuel Warning Light . . . . . . . . . 145
Low-Profile Tires . . . . . . . . . . . . . . . . 380
Lower Anchors and Tethers for Children (LATCH
System) . . . . . . . . . . . . . . . . . . . . . . . . 91
Lumbar Adjustment . . . . . . . . . . . . . . 56 Front Seats . . . . . . . . . . . . . . . . . . . . . 56
M
MaintenanceRecords . . . . . . . . . . . . . . . . . . . . . . 456
Maintenance and Care Additional . . . . . . . . . . . . . . . . . . . . . 449
Maintenance Schedule . . . . . . . . . 441
GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/-
Mexico-13337776) - 2020 - CRC - 8/27/19
496 Index
RoadsDriving, Wet . . . . . . . . . . . . . . . . . . 196
Roadside Assistance Program . . . . . . . . . . . . . . . . . . . . . . . 466
Roof Sunroof . . . . . . . . . . . . . . . . . . . . . . . . . 50
Rotation, Tires . . . . . . . . . . . . . . . . . . 396
Routing, Engine Drive Belt . . . . . . 461
Running the Vehicle While
Parked . . . . . . . . . . . . . . . . . . . . . . . . 220
S
Safety Defects ReportingCanadian Government . . . . . . . . 472
General Motors . . . . . . . . . . . . . . . 473
U.S. Government . . . . . . . . . . . . . 472
Safety Locks . . . . . . . . . . . . . . . . . . . . . 28
Safety System Check . . . . . . . . . . . . 70
Scheduling Appointments . . . . . . . 467
Seat Belts . . . . . . . . . . . . . . . . . . . . . . . 64 Care . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70
Extender . . . . . . . . . . . . . . . . . . . . . . . . 70
How to Wear Seat Belts
Properly . . . . . . . . . . . . . . . . . . . . . . . 65
Lap-Shoulder Belt . . . . . . . . . . . . . . 67
Reminders . . . . . . . . . . . . . . . . . . . . 135
Replacing after a Crash . . . . . . . . 71
Use During Pregnancy . . . . . . . . . . 69 Seats
Adjustment, Front . . . . . . . . . . . . . . . 54
Center Seat . . . . . . . . . . . . . . . . . . . . 55
Head Restraints . . . . . . . . . . . . . . . . 53
Heated and Ventilated Front . . . . 60
Heated, Rear . . . . . . . . . . . . . . . . . . . 63
Lumbar Adjustment, Front . . . . . . 56
Memory . . . . . . . . . . . . . . . . . . . . . . . . . 58
Power Adjustment, Front . . . . . . . 55
Rear . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62
Reclining Seatbacks . . . . . . . . . . . . 56
Underseat Storage . . . . . . . . . . . .113
Securing Child Restraints . . . . . . . . . . .104, 107, 108
Security Light . . . . . . . . . . . . . . . . . . . . . . . . . . 146
OnStar . . . . . . . . . . . . . . . . . . . . . . . 478
Vehicle . . . . . . . . . . . . . . . . . . . . . . . . . 36
Vehicle Alarm . . . . . . . . . . . . . . . . . . . 36
Service . . . . . . . . . . . . . . . . . . . . . . . . . 184 Accessories and
Modifications . . . . . . . . . . . . . . . . 329
Climate Control System . . . . . . . 177
Doing Your Own Work . . . . . . . . 330
Maintenance Records . . . . . . . . 456
Maintenance, General Information . . . . . . . . . . . . . . . . . . 439
Parts Identification . . . . . . . . . . . . 457 Service (cont'd)
Scheduling Appointments . . . . . 467
Service Electric Parking Brake Light . . . . . . . . . . . . . . . . . . . . 140
Services Special Application . . . . . . . . . . . 448
Servicing the Airbag . . . . . . . . . . . . . 82
Shift Lock Control Function Check, Automatic
Transmission . . . . . . . . . . . . . . . . . . 363
Shifting Into Park . . . . . . . . . . . . . . . . . . . . . . 217
Out of Park . . . . . . . . . . . . . . . . . . . 218
Side Blind Zone Alert (SBZA) . . . 274
Signals, Turn and
Lane-Change . . . . . . . . . . . . . . . . . 170
Snow Plow . . . . . . . . . . . . . . . . . . . . . 323
Special Application Services . . . . 448
Specifications and Capacities . . . . . . . . . . . . . . . . . . . . . 458
Speedometer . . . . . . . . . . . . . . . . . . . 130
Start Assist, Hill . . . . . . . . . . . . . . . . . 235
Start Vehicle, Remote . . . . . . . . . . . 25
Starter Switch Check . . . . . . . . . . . 363
Starting the Engine . . . . . . . . . . . . . 212
Steering . . . . . . . . . . . . . . . . . . . . . . . . 188 Fluid, Power . . . . . . . . . . . . . . . . . . 354
Heated Wheel . . . . . . . . . . . . . . . . .119