Chevrolet Silverado 2500 HD/3500 HD Owner Manual (GMNA-Localizing-U.
S./Canada/Mexico-14632154) - 2021 - CRC - 11/20/20
8 Keys, Doors, and Windows
{Warning
If the key is unintentionally rotated while
the vehicle is running, the ignition could
be moved out of the RUN position. This
could be caused by heavy items hanging
from the key ring,
or by large or long items attached to the
key ring that could be contacted by the
driver or steering wheel. If the ignition
moves out of the RUN position, the
engine will shut off, braking and steering
power assist may be impacted, and
airbags may not deploy. To reduce the
risk of unintentional rotation of the
ignition key, do not change the way the
ignition key and Remote Keyless Entry
(RKE) transmitter, if equipped, are
connected to the provided key rings.
The ignition key and key rings, and RKE
transmitter, if equipped, are designed to
work together as a system to reduce the
risk of unintentionally moving the key out
of the RUN position. The ignition key has a
small hole to allow attachment of the
provided key ring. It is important that any replacement ignition keys have a small hole.
See your dealer if a replacement key is
required.
The combination and size of the rings that
came with your keys were specifically
selected for your vehicle. The rings are
connected to the key like two links of a
chain to reduce the risk of unintentionally
moving the key out of the RUN position. Do
not add any additional items to the ring
attached to the ignition key. Attach
additional items only to the second ring,
and limit added items to a few essential
keys or small, light items no larger than an
RKE transmitter.
Interference from radio-frequency
identification (RFID) tags may prevent the
key from starting the vehicle. Keep RFID
tags away from the key when starting the
vehicle.
The key is used for the ignition, all door
locks, and the glove box.
If equipped with memory seats, keys 1 and 2
are linked to seating positions of memory 1
or 2. See
Memory Seats 046.
Programming Keys
Follow these procedures to program up to
eight keys to the vehicle.
Programming with Two Recognized Keys
To program a new key:
Chevrolet Silverado 2500 HD/3500 HD Owner Manual (GMNA-Localizing-U.
S./Canada/Mexico-14632154) - 2021 - CRC - 11/20/20
10 Keys, Doors, and Windows
Warning (Continued)
the path of a closing window. Do not
leave children in a vehicle with the
ignition key or an RKE transmitter.
If the vehicle has the Keyless Access system,
the transmitter has a button on the side of
the transmitter used to remove the key.
This key is used for the driver door and
glove box.
Press the button to remove the key. Never
pull the key out without pressing the
button.
See your dealer if a replacement key or
additional key is needed.
If it becomes difficult to turn a key, inspect
the key blade for debris. Periodically clean
with a brush or pick.
With an active OnStar or connected service
plan, an OnStar Advisor may remotely
unlock the vehicle. SeeOnStar Overview
0 412.
If locked out of the vehicle, see Roadside
Assistance Program 0404. If equipped with memory seats, RKE
transmitters 1 and 2 are linked to seating
positions of memory 1 or 2. See
Memory
Seats 046.
Remote Keyless Entry (RKE)
System
See Radio Frequency Statement 0409.
If there is a decrease in the Remote Keyless
Entry (RKE) operating range:
.Check the distance. The transmitter may
be too far from the vehicle.
.Check the location. Other vehicles or
objects may be blocking the signal.
.Check the transmitter's battery. See
“Battery Replacement” later in this
section.
.If the transmitter is still not working
correctly, see your dealer or a qualified
technician for service.
Remote Keyless Entry (RKE)
System Operation (Key Access)
The RKE transmitter functions may work up
to 60 m (197 ft) away from the vehicle.
Chevrolet Silverado 2500 HD/3500 HD Owner Manual (GMNA-Localizing-U.
S./Canada/Mexico-14632154) - 2021 - CRC - 11/20/20
Storage 91
Storage
Storage Compartments
Storage Compartments . . . . . . . . . . . . . . . . . 91
Glove Box . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91
Cupholders . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91
Underseat Storage . . . . . . . . . . . . . . . . . . . . . . 92
Rear Storage . . . . . . . . . . . . . . . . . . . . . . . . . . . 92
Center Console Storage . . . . . . . . . . . . . . . . . 92
Floor Console Storage . . . . . . . . . . . . . . . . . . 93
Additional Storage Features
Cargo Tie-Downs . . . . . . . . . . . . . . . . . . . . . . . 93
Storage Compartments{
Warning
Do not store heavy or sharp objects in
storage compartments. In a crash, these
objects may cause the cover to open and
could result in injury.
Glove Box
To access the upper glove box, pull up on
the handle.
To access the lower glove box, unlock with
the key and pull down on the handle.
Cupholders
Front
There may be cupholders on the center
front seat console armrest.
Rear
If equipped, pull the rear seat armrest down
to access the cupholders.
Chevrolet Silverado 2500 HD/3500 HD Owner Manual (GMNA-Localizing-U.
S./Canada/Mexico-14632154) - 2021 - CRC - 11/20/20
204 Climate Controls
The solar sensor, on top of the instrument
panel near the windshield, monitors the
solar heat.
The climate control system uses the sensor
information to adjust the temperature, fan
speed, recirculation, and air delivery mode
for best comfort.
Do not cover the sensor; otherwise the
automatic climate control system may not
work properly.
Air Vents
Use the sliding knobs on the center and side
air vents to change the direction of the
airflow.
Air vents blow warm air on the side
windows in cold weather. If Floor, Defog,
or Defrost modes are selected, a small
amount of air will come from the vents
close to the window.
To close the front a/c vents, move the
sliding knobs to the full down position.
To close the rear a/c vents, move the sliding
knobs to the full inboard position.Operation Tips
.Clear away any ice, snow, or leaves from
air inlets at the base of the windshield
that could block the flow of air into the
vehicle.
.Clear snow off the hood to improve
visibility and help decrease moisture
drawn into the vehicle.
.Keep the path under the front seats clear
of objects to help circulate the air inside
of the vehicle more effectively.
.Use of non-GM approved hood deflectors
can adversely affect the performance of
the system. Check with your dealer
before adding equipment to the outside
of the vehicle.
.Do not attach any devices to the air vent
slats. This will restrict airflow and may
cause damage to the air vents.
Maintenance
Passenger Compartment Air Filter
The filter reduces the dust, pollen, and other
airborne irritants from outside air that is
pulled into the vehicle.The filter should be replaced as part of
routine scheduled maintenance. See
Maintenance Schedule
0384. To find out
what type of filter to use, see Maintenance
Replacement Parts 0394.
1. Open the lower glove box door
completely.
Chevrolet Silverado 2500 HD/3500 HD Owner Manual (GMNA-Localizing-U.
S./Canada/Mexico-14632154) - 2021 - CRC - 11/20/20
Climate Controls 205
2. Push the dampener arm to the left untilit releases the glovebox.
3. Press the sides of the glove box doorinward and rotate the door downward to
remove.
4. Pull lever on left side of the filter doorand slide left, then remove the door.
Remove the old filter.
5. Install the new air filter.
6. Reinstall the filter door.
7. Reverse the steps to reinstall the glove box.
See your dealer if additional assistance is
needed.
Service
All vehicles have a label underhood that
identifies the refrigerant used in the vehicle.
The refrigerant system should only be
serviced by trained and certified technicians.
The air conditioning evaporator should never
be repaired or replaced by one from a
salvage vehicle. It should only be replaced
by a new evaporator to ensure proper and
safe operation.
During service, all refrigerants should be
reclaimed with proper equipment. Venting
refrigerants directly to the atmosphere is
harmful to the environment and may also
create unsafe conditions based on
inhalation, combustion, frostbite, or other
health-based concerns.
The air conditioning system requires periodic
maintenance. See Maintenance Schedule
0 384.
Chevrolet Silverado 2500 HD/3500 HD Owner Manual (GMNA-Localizing-U.
S./Canada/Mexico-14632154) - 2021 - CRC - 11/20/20
222 Driving and Operating
2. Secondary Load Areas
3. GM Approved Accessory MountingPoints
Structural members (1) and (2) are included
in the pickup box design. Additional
accessories should use these load points.
Depending on the accessory design, use a
spacer under the accessory at the load
points to remove gap. The holes for GM
approved accessories (3) are not intended for
aftermarket equipment. See
www.gmupfitter.com for additional pickup
box load bearing structural information.
Truck-Camper Loading Information
A vehicle-specific Truck-Camper Loading
Information label is attached to the
inside of the vehicle's glove box. This
label indicates if a slide-in camper can
be carried, how much of a load the
vehicle can carry, and how to correctly
spread out the load. It will help to
match the right slide-in camper to the
vehicle.
Your dealer can help make a good
vehicle-camper match and help
determine the Cargo Weight
Rating (CWR). When installing and loading a slide-in
camper, check the manufacturer's
instructions.
When carrying a slide-in camper, the
total cargo load of the vehicle is the
weight of the camper plus:
.Everything added to the camper after
it left the factory.
.Everything in the camper.
.All the people inside.
The CWR is the maximum weight of the
load the vehicle can carry. It does not
include the weight of the people inside.
But, use about 68 kg (150 lb) for
each seat.
The total cargo load must not be more
than the vehicle's CWR.
Refer to the Truck-Camper Loading
Information label in the glove box for
dimensions A and B as shown in the
following illustration.
Use the rear edge of the load floor for
measurement purposes. The
recommended location for the cargo
center of gravity is in zone C for the
CWR. It is the point where the mass of
a body is concentrated and,
if suspended at that point, would
balance the front and rear.
Here is an example of proper truck and
camper match:
Chevrolet Silverado 2500 HD/3500 HD Owner Manual (GMNA-Localizing-U.
S./Canada/Mexico-14632154) - 2021 - CRC - 11/20/20
Technical Data 397
Technical Data
Vehicle Identification
Vehicle Identification Number (VIN) . . . 397
Service Parts Identification . . . . . . . . . . . . 397
Vehicle Data
Capacities and Specifications . . . . . . . . . . 398
Engine Drive Belt Routing . . . . . . . . . . . . . 400
Vehicle Identification
Vehicle Identification
Number (VIN)
This legal identifier is in the front corner of
the instrument panel, on the driver side of
the vehicle. It can be seen through the
windshield from outside. The Vehicle
Identification Number (VIN) also appears on
the Vehicle Certification label and certificates
of title and registration.
Engine Identification
The eighth character in the VIN is the
engine code. This code identifies the
vehicle's engine, specifications, and
replacement parts. See“Engine
Specifications” underCapacities and
Specifications 0398 for the vehicle's
engine code.
Service Parts Identification
There may be a large barcode on the
certification label on the center pillar that
you can scan for the following information:
.Vehicle Identification Number (VIN)
.Model designation
.Paint information
.Production options
If there is not a large barcode on this label,
then you will find this same information
on a label inside of the glove box.
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