fuel CHEVROLET SILVERADO 2500HD 2021 Repair Manual

Chevrolet Silverado 2500 HD/3500 HD Owner Manual (GMNA-Localizing-U.
S./Canada/Mexico-14632154) - 2021 - CRC - 11/20/20
394 Service and Maintenance
UsageFluid/Lubricant
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. See your dealer.
Transfer Case (Four-Wheel Drive) DEXRON-VI Automatic Transmission Fluid. Windshield Washer Automotive windshield washer fluid that meets regional freeze protection requirements.
Maintenance Replacement Parts
Replacement parts identified below by name, part number, or specification can be obtained from your dealer.
If the vehicle has a diesel engine, see the Duramax diesel supplement.
Part GM Part Number ACDelco Part Number
Engine Air Cleaner/Filter
IWith high capacity air cleaner 84121219 A3244C
IWithout high capacity air cleaner 84121217 A3246C
Oil Filter 12690385 PF63E
Passenger Compartment Air Filter 13508023 CF185
Spark Plugs 12622441 41-114

Chevrolet Silverado 2500 HD/3500 HD Owner Manual (GMNA-Localizing-U.
S./Canada/Mexico-14632154) - 2021 - CRC - 11/20/20
398 Technical Data
Vehicle Data
Capacities and Specifications
The following approximate capacities are given in metric and English conversions. SeeRecommended Fluids and Lubricants0393.
If the vehicle has a diesel engine, see the Duramax diesel supplement.
Application Capacities
Metric English
Air Conditioning Refrigerant For the air conditioning system refrigerant type and charge amount, see the refrigerant label under the hood. See yourdealer for more information.
Engine Cooling System* 14.6 L 15.4 qt
Engine Oil with Filter 7.6 L 8.0 qt
Fuel Tank
I2500 Series and 3500 Series Standard Box (Except Double Cab Diesel) 136.3 L 36.0 gal
I2500 Series and 3500 Series Standard Box (Double Cab Diesel) 111.3 L 29.4 gal
I2500 Series and 3500 Series Long Box (Except Regular Cab Diesel) 136.3 L 36.0 gal
I2500 Series and 3500 Series Long Box (Regular Cab Diesel) 106.0 L 28.0 gal

Chevrolet Silverado 2500 HD/3500 HD Owner Manual (GMNA-Localizing-U.
S./Canada/Mexico-14632154) - 2021 - CRC - 11/20/20
Customer Information 405
Services Provided
.Emergency Fuel Delivery:Delivery of
enough fuel for the vehicle to get to the
nearest service station.
.Lock-Out Service: Service to unlock the
vehicle if you are locked out. A remote
unlock may be available if you have
OnStar. For security reasons, the driver
must present identification before this
service is given.
.Emergency Tow from a Public Road or
Highway: Tow to the nearest Chevrolet
dealer for warranty service, or if the
vehicle was in a crash and cannot be
driven. Assistance is not given when the
vehicle is stuck in the sand, mud,
or snow.
.Flat Tire Change: Service to change a flat
tire with the spare tire. The spare tire,
if equipped, must be in good condition
and properly inflated. It is the owner's
responsibility for the repair or
replacement of the tire if it is not covered
by the warranty.
.Battery Jump Start: Service to jump start
a dead battery.
.Trip Interruption Benefits and Assistance:
If your trip is interrupted due to a
warranty event, incidental expenses may be reimbursed within the Powertrain
warranty period. Items considered are
reasonable and customary hotel, meals,
rental car, or a vehicle being delivered
back to the customer, up to 500 miles.
Services Not Included in Roadside
Assistance
.Impound towing caused by violation of
any laws
.Legal fines
.Mounting, dismounting, or changing of
snow tires, chains, or other traction
devices
Service is not provided if a vehicle is in an
area that is not accessible to the service
vehicle or is not a regularly traveled or
maintained public road, which includes ice
and winter roads. Off-road use is not
covered.
Services Specific to Canadian-Purchased
Vehicles
.Fuel Delivery: Reimbursement is up to
7 liters. If available, diesel fuel delivery
may be restricted. Propane and other
fuels are not provided through this
service.
.Lock-Out Service: Vehicle registration is
required.
.Trip Interruption Benefits and Assistance:
Must be over 150 km from where your
trip was started to qualify.
Pre-authorization, original detailed
receipts, and a copy of the repair orders
are required. Once authorization has been
received, the Roadside Assistance advisor
will help to make arrangements and
explain how to receive payment.
.Alternative Service: If assistance cannot
be provided right away, the Roadside
Assistance advisor may give permission to
get local emergency road service. You will
receive payment, up to $100, after
sending the original receipt to Roadside
Assistance. Mechanical failures may be
covered, however any cost for parts and
labor for repairs not covered by the
warranty are the owner responsibility.
Scheduling Service Appointments
When the vehicle requires warranty service,
contact your dealer and request an
appointment. By scheduling a service
appointment and advising the service
consultant of your transportation needs,
your dealer can help minimize your
inconvenience.

Chevrolet Silverado 2500 HD/3500 HD Owner Manual (GMNA-Localizing-U.
S./Canada/Mexico-14632154) - 2021 - CRC - 11/20/20
406 Customer Information
If the vehicle cannot be scheduled into the
service department immediately, keep
driving it until it can be scheduled for
service, unless, of course, the problem is
safety related. If it is, please call your
dealership, let them know this, and ask for
instructions.
If your dealer requests you to bring the
vehicle for service, you are urged to do so
as early in the work day as possible to
allow for same-day repair.
Courtesy Transportation Program
To enhance your ownership experience, we
and our participating dealers are proud to
offer Courtesy Transportation, a customer
support program for vehicles with the
Bumper-to-Bumper (Base Warranty Coverage
period in Canada), extended powertrain,
and/or hybrid-specific warranties in both the
U.S. and Canada.
Several Courtesy Transportation options are
available to assist in reducing inconvenience
when warranty repairs are required.
Courtesy Transportation is not a part of the
New Vehicle Limited Warranty. A separate
manual entitled“Limited Warranty and Owner Assistance Information”
furnished
with each new vehicle provides detailed
warranty coverage information.
Transportation Options
Warranty service can generally be
completed while you wait. However, if you
are unable to do so, your dealer may offer
the following transportation options:
Shuttle Service
This includes one-way or round-trip shuttle
service within reasonable time and distance
parameters of your dealer's area.
Public Transportation or Fuel Reimbursement
If overnight warranty repairs are needed,
and public transportation is used, the
expense must be supported by original
receipts and within the maximum amount
allowed by GM. If U.S. customers arrange
their own transportation, limited
reimbursement for reasonable fuel expenses
may be available. Claim amounts should
reflect actual costs and be supported by
original receipts. See your dealer for
information. Courtesy Rental Vehicle
For an overnight warranty repair, the dealer
may provide an available courtesy rental
vehicle or provide for reimbursement of a
rental vehicle. Reimbursement is limited and
must be supported by original receipts as
well as a signed and completed rental
agreement and meet state/provincial, local,
and rental vehicle provider requirements.
Requirements vary and may include
minimum age requirements, insurance
coverage, credit card, etc. Additional fees
such as fuel, rental vehicle insurance, taxes,
levies, usage fees, excessive mileage,
or rental usage beyond the completion of
the repair are also your responsibility.
It may not be possible to provide a like
vehicle as a courtesy rental.
Additional Program Information
All program options, such as shuttle service,
may not be available at every dealer.
Contact your dealer for specific availability.
General Motors reserves the right to
unilaterally modify, change, or discontinue
Courtesy Transportation at any time and to
resolve all questions of claim eligibility
pursuant to the terms and conditions
described herein at its sole discretion.

Chevrolet Silverado 2500 HD/3500 HD Owner Manual (GMNA-Localizing-U.
S./Canada/Mexico-14632154) - 2021 - CRC - 11/20/20
410 Customer Information
and notify General Motors of Canada
Company. Call Transport Canada at
1-800-333-0510; go to:
www.tc.gc.ca/recalls (English)
www.tc.gc.ca/rappels (French)
or write to:
Transport Canada
Motor Vehicle Safety Directorate
Defect Investigations and Recalls
Division
80 Noel Street
Gatineau
,QC J8Z 0A1
Reporting Safety Defects to
General Motors
In addition to notifying NHTSA (or Transport
Canada) in a situation like this, notify
General Motors.
In the U.S., call 1-800-222-1020, or write:
Chevrolet Motor Division
Chevrolet Customer Assistance Center
P.O. Box 33170
Detroit, MI 48232-5170
In Canada, call 1-800-263-3777 (English) or
1-800-263-7854 (French), or write:General Motors of Canada Company
Customer Care Centre, Mail Code:
CA1-163-005
1908 Colonel Sam Drive
Oshawa, Ontario L1H 8P7
In Mexico, call 800-466-0811 or
800-508-0000.
In other Central America and Caribbean
Countries, call 52-555-901-2369.
Vehicle Data Recording and
Privacy
The vehicle has a number of computers that
record information about the vehicle’s
performance and how it is driven or used.
For example, the vehicle uses computer
modules to monitor and control engine and
transmission performance, to monitor the
conditions for airbag deployment and
deploy them in a crash, and, if equipped, to
provide antilock braking to help the driver
control the vehicle. These modules may
store data to help the dealer technician
service the vehicle or to help GM improve
safety or features. Some modules may also
store data about how the vehicle is
operated, such as rate of fuel consumption
or average speed. These modules may retain
personal preferences, such as radio presets,
seat positions, and temperature settings.
Cybersecurity
GM collects information about the use of
your vehicle including operational and safety
related information. We collect this
information to provide, evaluate, improve,
and troubleshoot our products and services
and to develop new products and services.
The protection of vehicle electronics systems
and customer data from unauthorized
outside electronic access or control is
important to GM. GM maintains appropriate
security standards, practices, guidelines and
controls aimed at defending the vehicle and
the vehicle service ecosystem against
unauthorized electronic access, detecting
possible malicious activity in related
networks, and responding to suspected
cybersecurity incidents in a timely,
coordinated and effective manner. Security
incidents could impact your safety or
compromise your private data. To minimize
security risks, please do not connect your
vehicle electronic systems to unauthorized
devices or connect your vehicle to any
unknown or untrusted networks (such as
Bluetooth, WIFI or similar technology). In

Chevrolet Silverado 2500 HD/3500 HD Owner Manual (GMNA-Localizing-U.
S./Canada/Mexico-14632154) - 2021 - CRC - 11/20/20
418 Connected Services
PressQ, then ask the Advisor to download
directions to the vehicle’s navigation system,
if equipped. After the call ends, the
navigation screen will provide prompts to
begin driving directions. Routes that are
sent to the navigation screen can only be
canceled through the navigation system.
See www.onstar.com (U.S.) or www.onstar.ca
(Canada).
Connections
The following services help with staying
connected.
For coverage maps, see www.onstar.com
(U.S.) or www.onstar.ca (Canada).
Ensuring Security
.Change the default passwords for the
Wi-Fi hotspot and myChevrolet mobile
application. Make these passwords
different from each other and use a
combination of letters and numbers to
increase the security.
.Change the default name of the SSID
(Service Set Identifier). This is your
network’s name that is visible to other
wireless devices. Choose a unique name
and avoid family names or vehicle
descriptions. Wi-Fi Hotspot (If Equipped)
The vehicle may have a built-in Wi-Fi
hotspot that provides access to the Internet
and web content at 4G LTE speed. Up to
seven mobile devices can be connected.
A data plan is required. Use the in-vehicle
controls only when it is safe to do so.
1. To retrieve Wi-Fi hotspot information, press
=to open the OnStar app on the
infotainment display, then select Wi-Fi
Hotspot. On some vehicles, touch Wi-Fi
or Wi-Fi Settings on the screen.
2. The Wi-Fi settings will display the Wi-Fi hotspot name (SSID), password, and on
some vehicles, the connection type (no
Internet connection, 3G, 4G, 4G LTE), and
signal quality (poor, good, excellent). The
LTE icon shows connection to Wi-Fi. It is
possible that the icon may not illuminate
even though the vehicle has an active
connection.
3. To change the SSID or password, press
Qor call 1-888-4ONSTAR to connect
with an Advisor. On some vehicles, the
SSID and password can be changed in
the Wi-Fi Hotspot menu. After initial set-up, your vehicle’s Wi-Fi
hotspot will connect automatically to your
mobile devices. Manage data usage by
turning Wi-Fi on or off on your mobile
device, using the myChevrolet mobile app,
or by contacting an OnStar Advisor. On
some vehicles, Wi-Fi can also be managed
from the Wi-Fi Hotspot menu.
MyChevrolet Mobile App (If Available)
Download the myChevrolet mobile app to
compatible Apple and Android smartphones.
Chevrolet users can access the following
services from a smartphone:
.Remotely start/stop the vehicle,
if factory-equipped.
.Lock/unlock doors, if equipped with
automatic locks.
.Activate the horn and lamps.
.Check the vehicle’s fuel level, oil life,
or tire pressure, if factory-equipped with
the Tire Pressure Monitor System.
.Send destinations to the vehicle.
.Locate the vehicle on a map (U.S.
market only).
.Turn the vehicle's Wi-Fi hotspot on/off,
manage settings, and monitor data
consumption, if equipped.
.Locate a dealer and schedule service.

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
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.
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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

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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