brake fluid CHEVROLET SILVERADO 2500HD 2021 Owner's Guide

Chevrolet Silverado 2500 HD/3500 HD Owner Manual (GMNA-Localizing-U.
S./Canada/Mexico-14632154) - 2021 - CRC - 11/20/20
390 Service and Maintenance
Footnotes—Maintenance Schedule
Additional Required Services - Severe
(1) Or every four years, whichever comes
first. If driving in dusty conditions, inspect
the filter at each oil change or more often
as needed. See Engine Air Cleaner/Filter
0 309.
(2) Or every two years, whichever comes
first. More frequent replacement may be
needed if the vehicle is driven in areas with
heavy traffic, poor air quality, areas with
high dust levels or are sensitive to
environmental allergens. Filter replacement
may also be needed if you notice reduced
airflow, windows fogging up, or odors. Your
local GM Service location can help you
determine when it is the right time to
replace your filter.
(3) Visually check all fuel and vapor lines
and hoses for proper attachment,
connection, routing, and condition.
(4) Do not directly power wash the transfer
case and/or front/rear axle output seals.
High pressure water can overcome the seals
and contaminate the fluid. Contaminated
fluid will decrease the life of the transfer
case and/or drive axles and should be
replaced. (5)
Or every five years, whichever comes
first. See Cooling System 0310.
(6) Or every 10 years, whichever comes first.
Inspect for fraying, excessive cracking,
or damage; replace, if needed.
(7) Replace brake fluid every five years. See
Brake Fluid 0317.
(8) Or every 12 months, whichever comes
first. See Wiper Blade Replacement 0322.
(9) Or every 10 years, whichever comes first.
See Gas Strut(s) 0323.
(10) Replace air conditioning desiccant every
seven years.
Special Application Services
.Vehicles with Dual Wheels: Check dual
wheel nut torque at 160, 1 600, and
10 000 km (100, 1,000, and 6,000 mi) of
driving. Repeat this service whenever a
tire/wheel is serviced or removed.
.Severe Commercial Use Vehicles Only:
Lubricate chassis components every oil
change.
.Have underbody flushing service
performed. See “Underbody Maintenance”
in Exterior Care 0373.
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 12-volt 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.

Chevrolet Silverado 2500 HD/3500 HD Owner Manual (GMNA-Localizing-U.
S./Canada/Mexico-14632154) - 2021 - CRC - 11/20/20
Service and Maintenance 391
.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 0393 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.
Hoses
Hoses transport fluids and should be
regularly inspected to ensure that there are
no cracks or leaks. With a multi-point
inspection, your dealer can inspect the hoses
and advise if replacement is needed.
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.

Chevrolet Silverado 2500 HD/3500 HD Owner Manual (GMNA-Localizing-U.
S./Canada/Mexico-14632154) - 2021 - CRC - 11/20/20
Service and Maintenance 393
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, see“Recommended Fluids and Lubricants”
in the Duramax diesel supplement.
Fluids and lubricants identified below by name or specification, including fluids or lubricants not listed here, can be obtained from your dealer.
Usage Fluid/Lubricant
Automatic Transmission (6-Speed Transmission) DEXRON-VI Automatic Transmission Fluid.
Automatic Transmission (10-Speed Transmission) DEXRON ULV Automatic Transmission Fluid.
Chassis Lubrication Chassis lubricant meeting requirements of NLGI #2, Category LB or GC-LB. Engine Coolant 50/50 mixture of clean, drinkable water and use only DEX-COOL coolant. See Cooling System
0 310.
Engine Oil Engine oil meeting the dexos1 specification of the proper SAE viscosity grade. ACDelco dexos1 full synthetic is recommended. See Engine Oil0305.
Front and Rear Axle Driveshaft Splines See your dealer.
Front Axle (Four-Wheel Drive) and Rear Axle See your dealer. Hydraulic Brake System DOT 3 Hydraulic Brake Fluid. See Brake Fluid0317.
Hydraulic Power Steering System GM Power Steering Fluid. See your dealer.

Chevrolet Silverado 2500 HD/3500 HD Owner Manual (GMNA-Localizing-U.
S./Canada/Mexico-14632154) - 2021 - CRC - 11/20/20
Index 421
AudioBluetooth . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 157
Automatic Dimming Mirrors . . . . . . . . . . . . . . . . . . . . . . . 33
Door Locks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
Emergency Braking (AEB) . . . . . . . . . . . . . . 259
Headlamp System . . . . . . . . . . . . . . . . . . . . . 136
Transmission . . . . . . . . . . . . . . . . . . . . . . . . . . . 232
Transmission Fluid . . . . . . . . . . . . . . . . . . . . . 308
Automatic Transmission Manual Mode . . . . . . . . . . . . . . . . . . . . . . . . . 235
Shift Lock Control Function Check . . . . . . 322
Auxiliary Roof Mounted Lamp . . . . . . . . . . . . . . . . . . . 139
Auxiliary Jack . . . . . . . . . . . . . . . . . . . . . . . . . . . . 156
Avoiding Untrusted Media Devices . . . . . . . . 153
Axle, Front . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 320
Axle, Rear . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 320
B
Battery Exterior Lighting Battery Saver . . . . . . . . 142
Load Management . . . . . . . . . . . . . . . . . . . . . . 141
Power Protection . . . . . . . . . . . . . . . . . . . . . . 142
Battery - North America . . . . . . . . . . . . .318, 367
Blade Replacement, Wiper . . . . . . . . . . . . . . . 322
Blind Spot Mirrors . . . . . . . . . . . . . . . . . . . . . . . . .33 Bluetooth
Overview . . . . . . . . . . . . . . . . . . . . . . . . . . 175, 176
Bluetooth Audio . . . . . . . . . . . . . . . . . . . . . . . . . . 157
Brake Parking, Electric . . . . . . . . . . . . . . . . . . . . . . . . 240
System Warning Light . . . . . . . . . . . . . . . . . . 113
Brake Pad Life System . . . . . . . . . . . . . . . . . . . 316
Brakes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 316
Antilock . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 240
Assist . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 241
Fluid . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 317
Pad Life System . . . . . . . . . . . . . . . . . . . . . . . 316
Braking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 208 Automatic Emergency (AEB) . . . . . . . . . . . 259
Break-In, New Vehicle . . . . . . . . . . . . . . . . . . . . 223
Bulb Replacement Center High-Mounted Stoplamp(CHMSL) and Cargo Lamp . . . . . . . . . . . . 327
Halogen Bulbs . . . . . . . . . . . . . . . . . . . . . . . . . 325
Headlamp Aiming . . . . . . . . . . . . . . . . . . . . . . 324
Headlamps . . . . . . . . . . . . . . . . . . . . . . . . . . . . 324
Headlamps, Front Turn Signal, Sidemarker, and Parking Lamps . . . . . . 325
License Plate Lamps . . . . . . . . . . . . . . . . . . . 328
Taillamps, Turn Signal, Stoplamps, and Back-up Lamps . . . . . . . . . . . . . . . . . . 326
Buying New Tires . . . . . . . . . . . . . . . . . . . . . . . . . 351
C
Calibration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 98
California Perchlorate Materials Requirements . . . 301
California Proposition
65 Warning . . . . . . . . . . . . . . . . . . .301, 318, 367, Back Cover
Camera Truck Bed . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
Canadian Vehicle Owners . . . . . . . . . . . . . . . . . . . 1
Capacities and Specifications . . . . . . . . . . . . . 398
Carbon Monoxide
Engine Exhaust . . . . . . . . . . . . . . . . . . . . . . . . 232
Tailgate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
Winter Driving . . . . . . . . . . . . . . . . . . . . . . . . . 215
Cargo Tie-Downs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 93
Caution, Danger, and Warning . . . . . . . . . . . . . .2
Center Console Storage . . . . . . . . . . . . . . . . . . . 92
Center High-Mounted Stoplamp (CHMSL) and Cargo Lamp . . . . . . . . . . . . . . 327
Center Seat . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44
Chains, Tire . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 354
Charging Wireless . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 99
Charging System Light . . . . . . . . . . . . . . . . . . . . 111
Check Engine Light (Malfunction Indicator) . . . . 111

Chevrolet Silverado 2500 HD/3500 HD Owner Manual (GMNA-Localizing-U.
S./Canada/Mexico-14632154) - 2021 - CRC - 11/20/20
Index 423
Driver Mode Control Light . . . . . . . . . . . . . . . . 117
DrivingAssistance Systems . . . . . . . . . . . . . . . . . . . . 257
Better Fuel Economy . . . . . . . . . . . . . . . . . . . 207
Characteristics and Towing Tips . . . . . . . . 268
Defensive . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 208
Hill and Mountain Roads . . . . . . . . . . . . . . 215
If the Vehicle is Stuck . . . . . . . . . . . . . . . . . 216
Impaired . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 208
Loss of Control . . . . . . . . . . . . . . . . . . . . . . . . 210
Off-Road . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 211
Off-Road Recovery . . . . . . . . . . . . . . . . . . . . . 210
Vehicle Load Limits . . . . . . . . . . . . . . . . . . . . . 217
Wet Roads . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 214
Winter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 215
Dual Automatic Climate Control
System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 201
E
E85 or FlexFuel . . . . . . . . . . . . . . . . . . . . . . . . . . 264
Electric Parking Brake . . . . . . . . . . . . . . . . . . . . 240
Electric Parking Brake Light . . . . . . . . . . . . . . . 113
Electrical Equipment, Add-On . . . . . . . . . . . . 297
Electrical SystemEngine Compartment Fuse Block . . . . . . . 329
Fuses and Circuit Breakers . . . . . . . . . . . . . 329
Instrument Panel Fuse Block . . . . . . 332, 334
Overload . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 328 Electronic Stability Control (ESC) Off
Light . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 116
Emergency OnStar . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 413
Engine Air Cleaner/Filter . . . . . . . . . . . . . . . . . . . . . . 309
Check Light (Malfunction Indicator) . . . . . 111
Compartment Overview . . . . . . . . . . . . . . . . 304
Coolant Temperature Gauge . . . . . . . . . . . 108
Coolant Temperature Warning Light . . . . 116
Cooling System . . . . . . . . . . . . . . . . . . . . . . . . 310
Drive Belt Routing . . . . . . . . . . . . . . . . . . . . 400
Exhaust . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 232
Fan . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 314
Heater . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 228
Oil Life System . . . . . . . . . . . . . . . . . . . . . . . . 307
Oil Pressure Gauge . . . . . . . . . . . . . . . . . . . . 107
Oil Pressure Light . . . . . . . . . . . . . . . . . . . . . . . 117
Overheated ProtectionOperating Mode . . . . . . . . . . . . . . . . . . . . . 314
Overheating . . . . . . . . . . . . . . . . . . . . . . . . . . . 312
Power Messages . . . . . . . . . . . . . . . . . . . . . . . 126
Running While Parked . . . . . . . . . . . . . . . . . 232
Starting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 227
Engine Air Filter Life System . . . . . . . . . . . . . 308
Entry Lighting . . . . . . . . . . . . . . . . . . . . . . . . . . . . 141
Equipment, Towing . . . . . . . . . . . . . . . . . . . . . . 276
Event Data Recorders . . . . . . . . . . . . . . . . . . . . . 411 Exit Lighting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 141
Extended Parking . . . . . . . . . . . . . . . . . . . . . . . . . 231
Extender, Seat Belt . . . . . . . . . . . . . . . . . . . . . . . 56
Exterior Cargo Lamps . . . . . . . . . . . . . . . . . . . . 139
Exterior Lamp Controls . . . . . . . . . . . . . . . . . . . .134
Exterior Lamps Off Reminder . . . . . . . . . . . . 136
Exterior Lighting Battery Saver . . . . . . . . . . .142
F
Fan
Engine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 314
Filter,
Engine Air Cleaner . . . . . . . . . . . . . . . . . . . . . 309
Fixed Mast Antenna . . . . . . . . . . . . . . . . . . . . . . 153
Flash-to-Pass . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 136
Flashers, Hazard Warning . . . . . . . . . . . . . . . . . 137
Flat Tire . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 355 Changing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 356
FlexFuel E85 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 264
Floor Console Storage . . . . . . . . . . . . . . . . . . . . . 93
Floor Mats . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .381
Fluid
Automatic Transmission . . . . . . . . . . . . . . . 308
Brakes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 317
Four-Wheel Drive Transfer Case . . . . . . . . 236
Power Steering . . . . . . . . . . . . . . . . . . . . . . . . 314
Washer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 315

Chevrolet Silverado 2500 HD/3500 HD Owner Manual (GMNA-Localizing-U.
S./Canada/Mexico-14632154) - 2021 - CRC - 11/20/20
426 Index
Lights (cont'd)High/Low Beam Changer . . . . . . . . . . . . . . 136
Hill Descent Control . . . . . . . . . . . . . . . . . . . . 114
Lane Departure Warning . . . . . . . . . . . . . . . . 115
Low Fuel Warning . . . . . . . . . . . . . . . . . . . . . . 118
Seat Belt Reminders . . . . . . . . . . . . . . . . . . . 109
Security . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 118
Service Electric Parking Brake . . . . . . . . . . . 113
Tire Pressure . . . . . . . . . . . . . . . . . . . . . . . . . . . . 117
Tow/Haul Mode . . . . . . . . . . . . . . . . . . . . . . . . 114
Traction Off . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 115
Limited-Slip Differential . . . . . . . . . . . . . . . . . . 245
Lock
Steering Column . . . . . . . . . . . . . . . . . . . . . . . . 28
Locking Rear Axle . . . . . . . . . . . . . . . . . . . . . . . . 245
Locks Automatic Door . . . . . . . . . . . . . . . . . . . . . . . . . 22
Delayed Locking . . . . . . . . . . . . . . . . . . . . . . . . 22
Door . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
Lockout Protection . . . . . . . . . . . . . . . . . . . . . . 22
Power Door . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
Safety . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
Loss of Control . . . . . . . . . . . . . . . . . . . . . . . . . . 210
Low Fuel Warning Light . . . . . . . . . . . . . . . . . . 118
Lower Anchors and Tethers for Children (LATCH System) . . . . . . . . . . . . . . . . 74
Lumbar Adjustment . . . . . . . . . . . . . . . . . . . . . . . 45 Front Seats . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45M
MaintenanceRecords . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 396
Maintenance and Care Additional . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 390
Maintenance Schedule . . . . . . . . . . . . . . . . . . . 384 Recommended Fluids andLubricants . . . . . . . . . . . . . . . . . . . . . . . . . . . . 393
Transfer Case . . . . . . . . . . . . . . . . . . . . . . . . . . 236
Malfunction Indicator Lamp . . . . . . . . . . . . . . . 111
Manual Mirrors . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
Manual Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . 235
Manual Windows . . . . . . . . . . . . . . . . . . . . . . . . . 38
Map Data Updates . . . . . . . . . . . . . . . . . . . . . . . 170
Maps . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 161
Media
Avoiding Untrusted Devices . . . . . . . . . . . . 153
Memory Seats . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46
Messages Engine Power . . . . . . . . . . . . . . . . . . . . . . . . . . 126
Vehicle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 125
Vehicle Speed . . . . . . . . . . . . . . . . . . . . . . . . . . 126
Mirror Rear Camera . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
Mirrors Automatic Dimming . . . . . . . . . . . . . . . . . . . . 33
Automatic Dimming Rearview . . . . . . . . . . 34
Blind Spot . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33 Mirrors (cont'd)
Convex . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
Folding . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
Heated . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
Manual . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
Manual Rearview . . . . . . . . . . . . . . . . . . . . . . . 34
Power . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
Tilt in Reverse . . . . . . . . . . . . . . . . . . . . . . . . . . 34
Trailer Tow . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
Mirrors, Interior Rearview . . . . . . . . . . . . . . . . . 34
Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 244 Driver Control . . . . . . . . . . . . . . . . . . . . . . . . . 244
Monitor System, Tire Pressure . . . . . . . . . . . 342
Multi-band Antenna . . . . . . . . . . . . . . . . . . . . . . 153
N
Navigation Connected Services . . . . . . . . . . . . . . . . . . . . 417
Destination . . . . . . . . . . . . . . . . . . . . . . . . . . . . 162
Using the System . . . . . . . . . . . . . . . . . . . . . . 158
Navigation Symbols . . . . . . . . . . . . . . . . . . . . . . 161
New Vehicle Break-In . . . . . . . . . . . . . . . . . . . . 223
Noise Control System . . . . . . . . . . . . . . . . . . . . 320
O
Odometer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 106 Trip . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 106
Off-Road . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 211 Driving . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 211

Chevrolet Silverado 2500 HD/3500 HD Owner Manual (GMNA-Localizing-U.
S./Canada/Mexico-14632154) - 2021 - CRC - 11/20/20
Index 427
Off-Road (cont'd)Recovery . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 210
Oil Engine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 305
Engine Oil Life System . . . . . . . . . . . . . . . . . 307
Engine Oil Pressure Gauge . . . . . . . . . . . . . 107
Pressure Light . . . . . . . . . . . . . . . . . . . . . . . . . . 117
Older Children, Restraints . . . . . . . . . . . . . . . . . 68
Online Owner Center . . . . . . . . . . . . . . . . . . . . 403
OnStar . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 411
OnStar Additional Information . . . . . . . . . . . .413
OnStar Emergency . . . . . . . . . . . . . . . . . . . . . . . .413
OnStar Overview . . . . . . . . . . . . . . . . . . . . . . . . . .412
OnStar Security . . . . . . . . . . . . . . . . . . . . . . . . . . .413
OnStar System . . . . . . . . . . . . . . . . . . . . . . 157, 168
Operating Mode Overheated Engine Protection . . . . . . . . . 314
Operation Fog Lamps . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 138
Outlets Power . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 98
Overheated Engine Protection Operating Mode . . . . . . . . . . . . . . . . . . . . . . . .314
Overheating, Engine . . . . . . . . . . . . . . . . . . . . . . 312
Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 144 Instrument Panel . . . . . . . . . . . . . . . . . . . . . . . . 4P
Park
Shifting Into . . . . . . . . . . . . . . . . . . . . . . . . . . . 230
Shifting Out of . . . . . . . . . . . . . . . . . . . . . . . . 231
Park Assist . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 249
Parking
Brake and P (Park) MechanismCheck . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 322
Extended . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 231
Over Things That Burn . . . . . . . . . . . . . . . . . 231
Parking or Backing Assistance Systems . . . . . . . . . . . . . . . . . . . . 249
Passenger Airbag Status Indicator . . . . . . . . .110
Passenger Compartment Air Filter . . . . . . . 204
Passenger Sensing System . . . . . . . . . . . . . . . . 62
Perchlorate Materials Requirements, California . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 301
Personalization Vehicle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 126
Phone Apple CarPlay and Android Auto . . . . . . . 180
Bluetooth . . . . . . . . . . . . . . . . . . . . . . . . . . 175, 176
Pickup Conversion to Chassis Cab . . . . . . . . 299
Port USB . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 153
Positioning Vehicle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 169 Power
Door Locks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
Mirrors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
Outlets . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 98
Protection, Battery . . . . . . . . . . . . . . . . . . . . . 142
Retained Accessory (RAP) . . . . . . . . . . . . . . 229
Seat Adjustment . . . . . . . . . . . . . . . . . . . . . . . . 44
Steering Fluid . . . . . . . . . . . . . . . . . . . . . . . . . . 314
Windows . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
Power Assist Steps . . . . . . . . . . . . . . . . . . . . . . . . 26
Pregnancy, Using Seat Belts . . . . . . . . . . . . . . 56
Privacy Vehicle Data Recording . . . . . . . . . . . . . . . . 410
Problems with Route Guidance . . . . . . . . . . 169
Program Courtesy Transportation . . . . . . . . . . . . . . . 406
Prohibited Fuels . . . . . . . . . . . . . . . . . . . . . . . . . 264
Proposition 65 Warning, California . . . . . . . . . . . . . . . . . . . . .301, 318, 367, Back Cover
Publication Ordering Information . . . . . . . . 408
R
Radio
HD Radio Technology . . . . . . . . . . . . . . . . . . . 151
Radio Data System (RDS) . . . . . . . . . . . . . . . . . 152
Radio Frequency Statement . . . . . . . . . . . . . . 409
Radio Reception . . . . . . . . . . . . . . . . . . . . . . . . . . 153

Chevrolet Silverado 2500 HD/3500 HD Owner Manual (GMNA-Localizing-U.
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Index 429
Seats (cont'd)Rear . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50
Reclining Seatbacks . . . . . . . . . . . . . . . . . . . . . 45
Underseat Storage . . . . . . . . . . . . . . . . . . . . . . 92
Securing Child Restraints . . . . . . . . . . . . . . 84, 87
Security Light . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 118
OnStar . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 413
Vehicle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
Vehicle Alarm . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
Service . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 205 Accessories and Modifications . . . . . . . . . 302
Climate Control System . . . . . . . . . . . . . . . . 199
Doing Your Own Work . . . . . . . . . . . . . . . . . 302
Maintenance Records . . . . . . . . . . . . . . . . . . 396
Maintenance, General Information . . . . . 383
Parts Identification . . . . . . . . . . . . . . . . . . . . . 397
Scheduling Appointments . . . . . . . . . . . . . . 405
Service Electric Parking Brake Light . . . . . . . 113
Services Special Application . . . . . . . . . . . . . . . . . . . . . 390
Servicing System . . . . . . . . . . . . . . . . . . . . . . . . 170
Servicing the Airbag . . . . . . . . . . . . . . . . . . . . . . 66
Settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 181
Shift Lock Control Function Check, Automatic Transmission . . . . . . . . . . . . . . . . 322
Shifting Into Park . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 230 Shifting (cont'd)
Out of Park . . . . . . . . . . . . . . . . . . . . . . . . . . . . 231
Side Blind Zone Alert (SBZA) . . . . . . . . . . . . . 260
Signals, Turn and Lane-Change . . . . . . . . . . . .138
Snow Plow . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 297
Software Updates . . . . . . . . . . . . . . . . . . . . . . . . 150
Special Application Services . . . . . . . . . . . . . . 390
Specifications and Capacities . . . . . . . . . . . . . 398
Speedometer . . . . . . . . . . . . . . . . . . . . . . . . . . . . 106
Start Assist, Hill . . . . . . . . . . . . . . . . . . . . . . . . . . 242
Start Vehicle, Remote . . . . . . . . . . . . . . . . . . . . . 20
Starter Switch Check . . . . . . . . . . . . . . . . . . . . . . 321
Starting the Engine . . . . . . . . . . . . . . . . . . . . . . 227
Steering . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 209 Fluid, Power . . . . . . . . . . . . . . . . . . . . . . . . . . . 314
Heated Wheel . . . . . . . . . . . . . . . . . . . . . . . . . . 96
Wheel Adjustment . . . . . . . . . . . . . . . . . . . . . . 96
Wheel Controls . . . . . . . . . . . . . . . . . . . . . . . . . 96
Steering Column Lock . . . . . . . . . . . . . . . . . . . . . 28
Steering Wheel Controls . . . . . . . . . . . . . . . . . 146
Steps Power Assist . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
Stoplamps and Back-up Lamps Bulb Replacement . . . . . . . . . . . . . . . . . . . . . . 326
Storage Rear . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 92
Storage Areas Center Console . . . . . . . . . . . . . . . . . . . . . . . . . 92 Storage Areas (cont'd)
Floor Console . . . . . . . . . . . . . . . . . . . . . . . . . . . 93
Glove Box . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91
Underseat . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 92
Storage Compartments . . . . . . . . . . . . . . . . . . . .91
Struts Gas . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 323
Stuck Vehicle . . . . . . . . . . . . . . . . . . . . . . . . . . . . 216
Sun Visors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
Sunroof . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
Symbols . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2 Navigation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 161
System Brake Pad Life . . . . . . . . . . . . . . . . . . . . . . . . . 316
Engine Air Filter Life . . . . . . . . . . . . . . . . . . . 308
Forward Collision Alert (FCA) . . . . . . . . . . . 257
Global Positioning . . . . . . . . . . . . . . . . . . . . . 168
Infotainment . . . . . . . . . . . . . . . . . . . . . . . . . . . . 411
Noise Control . . . . . . . . . . . . . . . . . . . . . . . . . . 320
OnStar . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 168
Systems
Driver Assistance . . . . . . . . . . . . . . . . . . . . . . 247
T
Tachometer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 106
Tailgate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .23

Chevrolet Silverado 2500 HD/3500 HD Owner Manual (GMNA-Localizing-U.
S./Canada/Mexico-14632154) - 2021 - CRC - 11/20/20
Index 431
Vehicle (cont'd)Canadian Owners . . . . . . . . . . . . . . . . . . . . . . . . . 1
Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 208
Identification Number (VIN) . . . . . . . . . . . . 397
Load Limits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 217
Messages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 125
Personalization . . . . . . . . . . . . . . . . . . . . . . . . 126
Remote Start . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Security . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
Speed Messages . . . . . . . . . . . . . . . . . . . . . . . 126
Towing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 369
Vehicle Ahead Indicator . . . . . . . . . . . . . . . . . . . 115
Vehicle Care
Tire Pressure . . . . . . . . . . . . . . . . . . . . . . . . . . . 341
Vehicle Data Recording and Privacy . . . . . . 410
Vehicle Positioning . . . . . . . . . . . . . . . . . . . . . . 169
Vehicle Security Steering Column Lock . . . . . . . . . . . . . . . . . . . 28
Ventilation, Air . . . . . . . . . . . . . . . . . . . . . . . . . . 204
Visors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
Voice Recognition . . . . . . . . . . . . . . . . . . . . . . . . 170
Voltmeter Gauge . . . . . . . . . . . . . . . . . . . . . . . . 109
W
Warning Brake System Light . . . . . . . . . . . . . . . . . . . . . 113
Caution and Danger . . . . . . . . . . . . . . . . . . . . . 2 Warning (cont'd)
Lane Departure (LDW) . . . . . . . . . . . . . . . . . 262
Warning Lights, Gauges, and Indicators . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 102
Warnings Hazard Flashers . . . . . . . . . . . . . . . . . . . . . . . . . 137
Washer Fluid . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 315
Wheels
Alignment and Tire Balance . . . . . . . . . . . . 354
Different Size . . . . . . . . . . . . . . . . . . . . . . . . . . 352
Replacement . . . . . . . . . . . . . . . . . . . . . . . . . . . 354
When It Is Time for New Tires . . . . . . . . . . . 350
Where to Put the Restraint . . . . . . . . . . . . . . . .73
Windows . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .37
Manual . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
Power . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
Rear . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
Windshield Replacement . . . . . . . . . . . . . . . . . . . . . . . . . . . 323
Wiper/Washer . . . . . . . . . . . . . . . . . . . . . . . . . . 97
Winter
Driving . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 215
Winter Tires . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 337
Wiper Blade Replacement . . . . . . . . . . . . . . . . 322
Wireless Charging . . . . . . . . . . . . . . . . . . . . . . . . 99