2021 CHEVROLET SILVERADO 2500HD change time

Chevrolet Silverado 2500 HD/3500 HD Owner Manual (GMNA-Localizing-U.
S./Canada/Mexico-14632154) - 2021 - CRC - 11/20/20
OnStar 415
Languages
The vehicle can be programmed to respond
in multiple languages. Press
Qand ask for
an Advisor. Advisors are available in English,
Spanish, and French. Available languages
may vary by country.
Potential Issues
OnStar cannot perform Remote Door Unlock
or Stolen Vehicle Assistance after the vehicle
has been off continuously for 10 days
without an ignition cycle. If the vehicle has
not been started for 10 days, OnStar can
contact Roadside Assistance or a locksmith
to help gain access to the vehicle.
Global Positioning System (GPS)
.Obstruction of the GPS can occur in a
large city with tall buildings; in parking
garages; around airports; in tunnels and
underpasses; or in an area with very
dense trees. If GPS signals are not
available, the OnStar system should still
operate to call OnStar. However, OnStar
could have difficulty identifying the exact
location.
.In emergency situations, OnStar can use
the last stored GPS location to send to
emergency responders. A temporary loss of GPS can cause loss of
the ability to send a Turn-by-Turn
Navigation route. The Advisor may give a
verbal route or may ask for a call back after
the vehicle is driven into an open area.
Cellular and GPS Antennas
Cellular reception is required for OnStar to
send remote signals to the vehicle. Do not
place items over or near the antenna to
prevent blocking cellular and GPS signal
reception.
Unable to Connect to OnStar Message
If there is limited cellular coverage or the
cellular network has reached maximum
capacity, this message may come on. Press
Qto try the call again or try again after
driving a few miles into another
cellular area.
Vehicle and Power Issues
OnStar services require a vehicle electrical
system, wireless service, and GPS satellite
technologies to be available and operating
for features to function properly. These
systems may not operate if the battery is
discharged or disconnected.
Add-on Electrical Equipment
The OnStar system is integrated into the
electrical architecture of the vehicle. Do not
add any electrical equipment. See Add-On
Electrical Equipment 0297. Added electrical
equipment may interfere with the operation
of the OnStar system and cause it to not
operate.
Vehicle Software Updates
OnStar or GM may remotely deliver
software updates or changes to the vehicle
without further notice or consent. These
updates or changes may enhance or
maintain safety, security, or the operation
of the vehicle or the vehicle systems.
Software updates or changes may affect or
erase data or settings that are stored in the
vehicle, such as saved navigation
destinations or pre-set radio stations.
Neither OnStar nor GM is responsible for
any affected or erased data or settings.
These updates or changes may also collect
personal information. Such collection is
described in the OnStar privacy statement or
separately disclosed at the time of
installation. These updates or changes may
also cause a system to automatically
communicate with GM servers to collect
information about vehicle system status,

Chevrolet Silverado 2500 HD/3500 HD Owner Manual (GMNA-Localizing-U.
S./Canada/Mexico-14632154) - 2021 - CRC - 11/20/20
Connected Services 419
.Request Roadside Assistance.
.Set a parking reminder with pin drop,
take a photo, make a note, and set a
timer.
.Connect with Chevrolet on social media.
Features are subject to change. For
myChevrolet mobile app information and
compatibility, see my.chevrolet.com.
An active OnStar or connected service plan
may be required. A compatible device,
factory-installed remote start, and power
locks are required. Data rates apply. See
www.onstar.com for details and system
limitations.
Remote Services
Contact an OnStar Advisor to unlock the
doors or sound the horn and flash the
lamps.
Marketplace
OnStar Advisors can provide offers from
restaurants and retailers on your route, help
locate hotels, or book a room. These services
vary by market.
Diagnostics
By monitoring and reporting on the vehicle's
key systems, OnStar Advanced Diagnostics,
if equipped, provides a way to keep up on
maintenance. Capabilities vary by model.
See www.onstar.com for details and system
limitations. Features are subject to change.
For updates on feature capabilities, see
my.chevrolet.com. Message and data rates
may apply.

Chevrolet Silverado 2500 HD/3500 HD Owner Manual (GMNA-Localizing-U.
S./Canada/Mexico-14632154) - 2021 - CRC - 11/20/20
424 Index
Fog Lamps . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .138
Folding Mirrors . . . . . . . . . . . . . . . . . . . . . . . . . . . .32
Forward Collision Alert (FCA) System . . . . 257
Four-Wheel Drive . . . . . . . . . . . . . . . . . . . 236, 320
Four-Wheel-Drive Light . . . . . . . . . . . . . . . . . . . . 114
Frequency StatementRadio . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 409
Front Axle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 320
Front Fog Lamp Light . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 118
Front Seats
Adjustment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
Heated and Ventilated . . . . . . . . . . . . . . . . . . 49
Fuel Additives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 264
Economy, Driving for Better . . . . . . . . . . . 207
Filling a Portable Fuel Container . . . . . . . 267
Filling the Tank . . . . . . . . . . . . . . . . . . . 265, 266
Foreign Countries . . . . . . . . . . . . . . . . . . . . . . 264
Gauge . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 106
Low Fuel Warning Light . . . . . . . . . . . . . . . . 118
Prohibited Fuels . . . . . . . . . . . . . . . . . . . . . . . 264
Recommended . . . . . . . . . . . . . . . . . . . . . . . . . 263
Top Tier . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 263
Full-Size Spare Tire . . . . . . . . . . . . . . . . . . . . . . . 366
Fuses
Engine Compartment Fuse Block . . . . . . . 329
Fuses and Circuit Breakers . . . . . . . . . . . . . 329 Fuses (cont'd)
Instrument Panel Fuse Block . . . . . . 332, 334
G
Garage Door Opener . . . . . . . . . . . . . . . . . . . . . . 131
Programming . . . . . . . . . . . . . . . . . . . . . . . . . . . 131
Gas Strut(s) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 323
Gauges Engine Coolant Temperature . . . . . . . . . . . 108
Engine Oil Pressure . . . . . . . . . . . . . . . . . . . . 107
Fuel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 106
Odometer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 106
Speedometer . . . . . . . . . . . . . . . . . . . . . . . . . . 106
Tachometer . . . . . . . . . . . . . . . . . . . . . . . . . . . . 106
Trip Odometer . . . . . . . . . . . . . . . . . . . . . . . . . 106
Voltmeter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 109
Warning Lights and Indicators . . . . . . . . . 102
General Information Service and Maintenance . . . . . . . . . . . . . . 383
Towing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 268
Vehicle Care . . . . . . . . . . . . . . . . . . . . . . . . . . . 301
Glass Replacement . . . . . . . . . . . . . . . . . . . . . . . 323
Global Positioning System (GPS) . . . . . . . . . 168
Glove Box . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .91
GM Mobility Reimbursement Program . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 404
Guidance Problems with the Route . . . . . . . . . . . . . . 169
H
Halogen Bulbs . . . . . . . . . . . . . . . . . . . . . . . . . . . 325
Hazard Warning Flashers . . . . . . . . . . . . . . . . . 137
HD Radio Technology . . . . . . . . . . . . . . . . . . . . . 151
Head Restraints . . . . . . . . . . . . . . . . . . . . . . . . . . . 42
Head-up Display . . . . . . . . . . . . . . . . . . . . . . . . . . 123
HeadlampsAiming . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 324
Automatic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 136
Bulb Replacement . . . . . . . . . . . . . . . . . . . . . . 324
Daytime Running Lamps (DRL) . . . . . . . . . 136
Flash-to-Pass . . . . . . . . . . . . . . . . . . . . . . . . . . . 136
Headlamps, Front Turn Signal,Sidemarker, and Parking Lamps . . . . . . 325
High-Beam On Light . . . . . . . . . . . . . . . . . . . . 118
High/Low Beam Changer . . . . . . . . . . . . . . 136
Lamps On Reminder . . . . . . . . . . . . . . . . . . . . 118
Heated Rear Seats . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51
Steering Wheel . . . . . . . . . . . . . . . . . . . . . . . . . 96
Heated and Ventilated Front Seats . . . . . . . 49
Heated Mirrors . . . . . . . . . . . . . . . . . . . . . . . . . . . .33
Heater Engine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 228
Heating . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .199, 201
High-Beam On Light . . . . . . . . . . . . . . . . . . . . . . 118
Hill and Mountain Roads . . . . . . . . . . . . . . . . . 215
Hill Descent Control (HDC) . . . . . . . . . . . . . . . 244

Chevrolet Silverado 2500 HD/3500 HD Owner Manual (GMNA-Localizing-U.
S./Canada/Mexico-14632154) - 2021 - CRC - 11/20/20
Index 425
Hill Descent Control Light . . . . . . . . . . . . . . . . . 114
Hill Start Assist (HSA) . . . . . . . . . . . . . . . . . . . . 242
Hood . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 302
Horn . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 97
How to Wear Seat Belts Properly . . . . . . . . . .52
HVAC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .199, 201
I
If the System Needs Service . . . . . . . . . . . . . 170
Ignition Positions . . . . . . . . . . . . . . . . . . . 224, 226
Ignition Transmission Lock Check . . . . . . . . 322
Immobilizer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
IndicatorVehicle Ahead . . . . . . . . . . . . . . . . . . . . . . . . . . 115
Infants and Young Children, Restraints . . . . 69
Information Publication Ordering . . . . . . . . . . . . . . . . . . . 408
Infotainment System . . . . . . . . . . . . . . . . . . . . . 411
Instrument Cluster . . . . . . . . . . . . . . . . . . . . . . . 102
Instrument Panel Overview . . . . . . . . . . . . . . . . 4
Interior Rearview Mirrors . . . . . . . . . . . . . . . . . 34
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . 1, 143
J
Jack Auxiliary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 156
Jump Starting - North America . . . . . . . . . . . 367
K
Keyless Entry
Remote (RKE) System . . . . . . . . . . . . . . . . 10, 13
Keys . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7, 9
L
Labeling, Tire Sidewall . . . . . . . . . . . . . . . . . . . 338
Lamps Auxiliary Roof Mounted Lamp . . . . . . . . . 139
Daytime Running (DRL) . . . . . . . . . . . . . . . . 136
Dome . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 140
Exterior Cargo . . . . . . . . . . . . . . . . . . . . . . . . . 139
Exterior Controls . . . . . . . . . . . . . . . . . . . . . . . 134
Exterior Lamps Off Reminder . . . . . . . . . . 136
Exterior Lighting Battery Saver . . . . . . . . 142
License Plate . . . . . . . . . . . . . . . . . . . . . . . . . . . 328
Malfunction Indicator (CheckEngine) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 111
On Reminder . . . . . . . . . . . . . . . . . . . . . . . . . . . 118
Reading . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 141
Lane Change Alert (LCA) . . . . . . . . . . . . . . . . . 261
Lane Departure Warning (LDW) . . . . . . . . . . 262
Lane Departure Warning Light . . . . . . . . . . . . 115
Lap-Shoulder Belt . . . . . . . . . . . . . . . . . . . . . . . . . 54
LATCH System Replacing Parts after a Crash . . . . . . . . . . . 84
LATCH, Lower Anchors and Tethers for Children . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74 LED Lighting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 325
Lighting
Entry . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 141
Exit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 141
Illumination Control . . . . . . . . . . . . . . . . . . . 140
LED . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 325
Task . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 139
Lights Airbag Readiness . . . . . . . . . . . . . . . . . . . . . . 110
Antilock Brake System (ABS)Warning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 114
Brake System Warning . . . . . . . . . . . . . . . . . 113
Charging System . . . . . . . . . . . . . . . . . . . . . . . 111
Check Engine (Malfunction Indicator) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 111
Cruise Control . . . . . . . . . . . . . . . . . . . . . . . . . . 119
Door Ajar . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 119
Driver Mode Control . . . . . . . . . . . . . . . . . . . . 117
Electric Parking Brake . . . . . . . . . . . . . . . . . . . 113
Electronic Stability Control (ESC), Off . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 116
Engine Coolant Temperature Warning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 116
Engine Oil Pressure . . . . . . . . . . . . . . . . . . . . . 117
Flash-to-Pass . . . . . . . . . . . . . . . . . . . . . . . . . . . 136
Four-Wheel-Drive . . . . . . . . . . . . . . . . . . . . . . . 114
Front Fog Lamp . . . . . . . . . . . . . . . . . . . . . . . . . 118
High-Beam On . . . . . . . . . . . . . . . . . . . . . . . . . . 118

Chevrolet Silverado 2500 HD/3500 HD Owner Manual (GMNA-Localizing-U.
S./Canada/Mexico-14632154) - 2021 - CRC - 11/20/20
430 Index
TaillampsBulb Replacement . . . . . . . . . . . . . . . . . . . . . . 326
Task Lighting . . . . . . . . . . . . . . . . . . . . . . . . . . . . 139
Teen Driver . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .187
Text Telephone (TTY) Users . . . . . . . . . . . . . . 403
Theft-Deterrent Systems . . . . . . . . . . . . . . . . . . 29 Immobilizer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
Time . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 98
Tires . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 336 All-Season . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 337
All-Terrain . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 337
Buying New Tires . . . . . . . . . . . . . . . . . . . . . . 351
Chains . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 354
Changing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 356
Designations . . . . . . . . . . . . . . . . . . . . . . . . . . . 339
Different Size . . . . . . . . . . . . . . . . . . . . . . . . . . 352
Full-Size Spare . . . . . . . . . . . . . . . . . . . . . . . . . 366
If a Tire Goes Flat . . . . . . . . . . . . . . . . . . . . . 355
Inspection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 348
Pressure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 341
Pressure Light . . . . . . . . . . . . . . . . . . . . . . . . . . 117
Pressure Monitor Operation . . . . . . . . . . . 343
Pressure Monitor System . . . . . . . . . . . . . . 342
Rotation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 348
Sidewall Labeling . . . . . . . . . . . . . . . . . . . . . . 338
Terminology and Definitions . . . . . . . . . . . 339
Uniform Tire Quality Grading . . . . . . . . . . 352
Wheel Alignment and Tire Balance . . . . 354 Tires (cont'd)
Wheel Replacement . . . . . . . . . . . . . . . . . . . . 354
When It Is Time for New Tires . . . . . . . . . 350
Winter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 337
Top Tier Fuel . . . . . . . . . . . . . . . . . . . . . . . . . . . . 263
Tow/Haul Mode . . . . . . . . . . . . . . . . . . . . . . . . . 235
Tow/Haul Mode Light . . . . . . . . . . . . . . . . . . . . 114
Towing Driving Characteristics . . . . . . . . . . . . . . . . . 268
Equipment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 276
General Information . . . . . . . . . . . . . . . . . . . 268
Recreational Vehicle . . . . . . . . . . . . . . . . . . . 370
Trailer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 272
Trailer Sway Control (TSC) . . . . . . . . . . . . . 285
Vehicle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 369
Traction
Limited-Slip Differential . . . . . . . . . . . . . . . . 245
Off Light . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 115
Traction Control/Electronic Stability Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 242
Trademarks and License Agreements . . . . . 190
Trailer
Sway Control (TSC) . . . . . . . . . . . . . . . . . . . . 285
Tow Mirrors . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
Towing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 272
Trailer Towing
App . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 286
Trailering App . . . . . . . . . . . . . . . . . . . . . . . . . . . 286 Transfer Case . . . . . . . . . . . . . . . . . . . . . . . . . . . . 236
Transmission
Automatic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 232
Fluid, Automatic . . . . . . . . . . . . . . . . . . . . . . . 308
Transportation Program, Courtesy . . . . . . . 406
Trip Odometer . . . . . . . . . . . . . . . . . . . . . . . . . . . 106
Truck Bed Camera Rearview Mirror . . . . . . . .37
Truck-Camper Loading Information . . . . . . . 222
Turn and Lane-Change Signals . . . . . . . . . . . .138
Turn Signal Bulb Replacement . . . . . . . . . . . . . . . . . . . . . . 326
U
Underseat Storage . . . . . . . . . . . . . . . . . . . . . . . . 92
Uniform Tire Quality Grading . . . . . . . . . . . . 352
Universal Remote System . . . . . . . . . . . . . . . . . 131Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 133
Programming . . . . . . . . . . . . . . . . . . . . . . . . . . . 131
Updates Map Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 170
Software . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 150
USB Port . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 153
Using the Navigation System . . . . . . . . . . . . .158
Using the System . . . . . . . . . . . . . . . . . . . . . . . . .147
Using This Manual . . . . . . . . . . . . . . . . . . . . . . . . . .2
V
Vehicle Alarm System . . . . . . . . . . . . . . . . . . . . . . . . . . 27