
GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
260 Driving and Operating .
Pressing the accelerator more
than one-quarter of the
way down.
.
Turning the ignition off.
Retained Accessory
Power (RAP) The following vehicle accessories
can be used for up to 10 minutes
after the engine is turned off:
.
Audio System
.
Power Windows
.
OnStar System (if equipped)
.
Sunroof (if equipped)
These features work when the key
is in ON/RUN or ACC/
ACCESSORY. Once the key is
turned from ON/RUN to LOCK/OFF,
the windows and sunroof continue
to work up to 10 minutes or until any
door is opened. The radio continues
to work for up to 10 minutes or until
the driver door is opened. Accessory Power Outlets (APOs)
The vehicle may have Accessory
Power Outlets (APOs) in several
locations. See Power Outlets 0 133 .
The APOs in the console or center
seat position are powered by
Retained Accessory Power (RAP).
They will continue to work for up to
10 minutes after the key is turned
from ON/RUN to LOCK/OFF, or until
the driver door is opened.
The APOs on the center stack come
from the factory powered directly
from the vehicle battery, and supply
accessory power at all times,
regardless of ignition key position.
If electronic items are left plugged
into these APOs for long periods of
time with the vehicle off, the vehicle
battery could be drained. The
vehicle may not start if the battery is
allowed to drain for an extended
period of time. Engine Coolant Heater The engine heater can provide
easier starting and better fuel
economy during engine warm-up in
cold weather conditions at or below
− 18 °C (0 °F). Vehicles with an
engine heater should be plugged in
at least four hours before starting.
An internal thermostat in the
plug-end of the cord may exist,
which will prevent engine coolant
heater operation at temperatures
above − 18 °C (0 °F).
If the vehicle has a diesel engine,
see the Duramax diesel
supplement.
{ Warning
Do not plug in the engine block
heater while the vehicle is parked
in a garage or under a carport.
Property damage or personal
injury may result. Always park the
vehicle in a clear open area away
from buildings or structures.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
386 Vehicle Care Fuses Usage
2 Accessory power
outlet 4
7 Body control module 4
8 Body control module 8
9 Rear seat
entertainment
10 Cargo lamp
15 Steering wheel
controls
18 Radio
19 –
20 Sunroof
23 Airbag/Info
26 Export/Power take off/
Special equipment
option/Battery 1
27 Obstacle detection/
USB ports
28 Body control module 2
32 Special equipment
option/Battery 2 Fuses Usage
35 Air conditioning
inverter
36 Amplifier
37 Battery system
39 Rear sliding window
42 Right door window
motor
43 Front blower
44 Special equipment
option
45 Body control module 6
46 Body control module 7
47 Passenger seat
Relays Usage
50 Retained accessory
power
51 Rear sliding
window open
52 Rear sliding window
close Instrument Panel Fuse
Block (Left)
The left instrument panel fuse block
access door is on the driver side
edge of the instrument panel.
Pull off the cover to access the fuse
block.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
Service and Maintenance 449.
Check tire inflation pressures.
See Tire Pressure 0 397 .
.
Inspect tire wear. See Tire
Inspection 0 404 .
.
Visually check for fluid leaks.
.
Inspect engine air cleaner filter.
See Engine Air Cleaner/Filter
0 358 .
.
Inspect brake system. See
Exterior Care 0 435 .
.
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 0 435 . 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 0 75 . .
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 0 435 .
.
Check starter switch. See Starter
Switch Check 0 374 .
.
Check automatic transmission
shift lock control function. See
Automatic Transmission Shift
Lock Control Function Check
0 374 .
.
Check ignition transmission lock.
See Ignition Transmission Lock
Check 0 374 .
.
Check parking brake and
automatic transmission park
mechanism. See Park Brake and
P (Park) Mechanism Check
0 375 . .
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. If the hold
open ability is low, service the
gas strut. See Gas Strut(s)
0 376 .
.
Inspect sunroof track and seal,
if equipped. See Sunroof 0 55 .
.
Verify spare tire key lock
operation and lubricate as
needed. See Tire Changing
0 415 .

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
500 Index Restraints
Where to Put . . . . . . . . . . . . . . . . . . . 98
Retained Accessory
Power (RAP) . . . . . . . . . . . . . . . . . . 260
Reverse Tilt Mirrors . . . . . . . . . . . . . . 51
Roads
Driving, Wet . . . . . . . . . . . . . . . . . . 244
Roadside Assistance
Program . . . . . . . . . . . . . . . . . . . . . . . 469
Roof
Sunroof . . . . . . . . . . . . . . . . . . . . . . . . . 55
Rotation, Tires . . . . . . . . . . . . . . . . . . 405
Routing, Engine Drive Belt . . . . . . 464
Running the Vehicle While
Parked . . . . . . . . . . . . . . . . . . . . . . . . 265
S Safety Defects Reporting
Canadian Government . . . . . . . . 476
General Motors . . . . . . . . . . . . . . . 477
U.S. Government . . . . . . . . . . . . . 476
Safety Locks . . . . . . . . . . . . . . . . . . . . . 42
Safety System Check . . . . . . . . . . . . 75
Satellite Radio . . . . . . . . . . . . . . . . . . 192
Scheduling Appointments . . . . . . . 471
Seat Belts . . . . . . . . . . . . . . . . . . . . . . . 69
Care . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76
Extender . . . . . . . . . . . . . . . . . . . . . . . . 75 Seat Belts (cont'd)
How to Wear Seat Belts
Properly . . . . . . . . . . . . . . . . . . . . . . . 70
Lap Belt . . . . . . . . . . . . . . . . . . . . . . . . 75
Lap-Shoulder Belt . . . . . . . . . . . . . . 71
Reminders . . . . . . . . . . . . . . . . . . . . 146
Replacing after a Crash . . . . . . . . 76
Use During Pregnancy . . . . . . . . . . 74
Seats
Adjustment, Front . . . . . . . . . . . . . . . 59
Center Seat . . . . . . . . . . . . . . . . . . . . 59
Head Restraints . . . . . . . . . . . . . . . . 58
Heated and Ventilated Front . . . . 65
Lumbar Adjustment, Front . . . . . . 60
Memory . . . . . . . . . . . . . . . . . . . . . . . . . 62
Power Adjustment, Front . . . . . . . 60
Rear . . . . . . . . . . . . . . . . . . . . . . . . 66, 68
Reclining Seatbacks . . . . . . . . . . . . 61
Securing Child
Restraints . . . . . . . . . . . 111, 114, 115
Security
Light . . . . . . . . . . . . . . . . . . . . . . . . . . 157
OnStar . . . . . . . . . . . . . . . . . . . . . . . 481
Vehicle . . . . . . . . . . . . . . . . . . . . . . . . . 44
Vehicle Alarm . . . . . . . . . . . . . . . . . . . 44
Service . . . . . . . . . . . . . . . . . . . . . . . . . 233
Accessories and
Modifications . . . . . . . . . . . . . . . . 343 Service (cont'd)
Climate Control
System . . . . . . . . . . . . . . . . . 224, 226
Doing Your Own Work . . . . . . . . 344
Maintenance Records . . . . . . . . 459
Maintenance, General
Information . . . . . . . . . . . . . . . . . . 446
Parts Identification Label . . . . . 460
Publications Ordering
Information . . . . . . . . . . . . . . . . . . 474
Scheduling Appointments . . . . . 471
Services
Special Application . . . . . . . . . . . 453
Servicing the Airbag . . . . . . . . . . . . . 90
Shift Lock Control Function
Check, Automatic
Transmission . . . . . . . . . . . . . . . . . . 374
Shifting
Into Park . . . . . . . . . . . . . . . . . . . . . . 262
Out of Park . . . . . . . . . . . . . . . . . . . 263
Signals, Turn and
Lane-Change . . . . . . . . . . . . . . . . . 181
Snow Plow . . . . . . . . . . . . . . . . . . . . . 337
Software Updates . . . . . . . . . . . . . . 189
Special Application Services . . . . 453
Specifications and
Capacities . . . . . . . . . . . . . . . . . . . . . 461
Speedometer . . . . . . . . . . . . . . . . . . . 142

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
Index 501StabiliTrak
OFF Light . . . . . . . . . . . . . . . . . . . . . 154
Start Assist, Hill . . . . . . . . . . . . . . . . . 282
Start Vehicle, Remote . . . . . . . . . . . 39
Starter Switch Check . . . . . . . . . . . 374
Starting the Engine . . . . . . . . . . . . . 258
Steering . . . . . . . . . . . . . . . . . . . . . . . . 237
Fluid, Power . . . . . . . . . . . . . . . . . . 365
Heated Wheel . . . . . . . . . . . . . . . . 130
Wheel Adjustment . . . . . . . . . . . . 129
Wheel Controls . . . . . . . . . . . . . . . 129
Steps
Power Assist . . . . . . . . . . . . . . . . . . . 43
Stoplamps and Back-up Lamps
Bulb Replacement . . . . . . . . . . . . 378
Storage Areas
Center Console . . . . . . . . . . . . . . . 125
Floor Console . . . . . . . . . . . . . . . . 126
Glove Box . . . . . . . . . . . . . . . . . . . . 124
Instrument Panel . . . . . . . . . . . . . 124
Sunglasses . . . . . . . . . . . . . . . . . . . 125
Storage Compartments . . . . . . . . . 124
Struts
Gas . . . . . . . . . . . . . . . . . . . . . . . . . . . 376
Stuck Vehicle . . . . . . . . . . . . . . . . . . . 247
Sun Visors . . . . . . . . . . . . . . . . . . . . . . . 55
Sunglass Storage . . . . . . . . . . . . . . . 125
Sunroof . . . . . . . . . . . . . . . . . . . . . . . . . . 55 Switches
Airbag On-Off . . . . . . . . . . . . . . . . . . . 84
Symbols . . . . . . . . . . . . . . . . . . . . . . . . . . 3
System
Forward Collision
Alert (FCA) . . . . . . . . . . . . . . . . . . 292
Infotainment . . . . . . . . . . . . . 186, 478
Noise Control . . . . . . . . . . . . . . . . . 373
Systems
Driver Assistance . . . . . . . . . . . . . 288
T Tachometer . . . . . . . . . . . . . . . . . . . . . 142
Tailgate . . . . . . . . . . . . . . . . . . . . . . . . . . 43
Taillamps
Bulb Replacement . . . . . . . . . . . . 378
Text Telephone (TTY) Users . . . . 468
Theft-Deterrent Systems . . . . . . . . . 46
Immobilizer . . . . . . . . . . . . . . . . . . . . . 46
Throttle, Adjustable . . . . . . . . . . . . . 256
Time . . . . . . . . . . . . . . . . . . . . . . . . . . . . 132
Tires . . . . . . . . . . . . . . . . . . . . . . . . . . . . 389
All-Season . . . . . . . . . . . . . . . . . . . . 389
All-Terrain . . . . . . . . . . . . . . . . . . . . 391
Buying New Tires . . . . . . . . . . . . . 408
Chains . . . . . . . . . . . . . . . . . . . . . . . . 413
Changing . . . . . . . . . . . . . . . . . . . . . 415
Designations . . . . . . . . . . . . . . . . . 393 Tires (cont'd)
Different Size . . . . . . . . . . . . . . . . . 409
Full-Size Spare . . . . . . . . . . . . . . . 425
If a Tire Goes Flat . . . . . . . . . . . . 413
Inspection . . . . . . . . . . . . . . . . . . . . 404
Low Profile . . . . . . . . . . . . . . . . . . . 390
Pressure . . . . . . . . . . . . . . . . . 397, 399
Pressure Light . . . . . . . . . . . . . . . . 156
Pressure Monitor Operation . . 400
Pressure Monitor System . . . . . 399
Rotation . . . . . . . . . . . . . . . . . . . . . . 405
Sidewall Labeling . . . . . . . . . . . . . 391
Terminology and Definitions . . 395
Uniform Tire Quality
Grading . . . . . . . . . . . . . . . . . . . . . 410
Wheel Alignment and Tire
Balance . . . . . . . . . . . . . . . . . . . . . .411
Wheel Replacement . . . . . . . . . . 412
When It Is Time for New
Tires . . . . . . . . . . . . . . . . . . . . . . . . 407
Winter . . . . . . . . . . . . . . . . . . . . . . . . 390
Tow/Haul Mode . . . . . . . . . . . . . . . . . 271
Tow/Haul Mode Light . . . . . . . . . . . 153
Towing
Driving Characteristics . . . . . . . . 303
Equipment . . . . . . . . . . . . . . . . . . . . 325
General Information . . . . . . . . . . 303
Recreational Vehicle . . . . . . . . . . 430