CHEVROLET SILVERADO 2500HD 2021 Owner's Manual

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
392 Service and Maintenance
.Trained dealer technicians can inspect and
recommend the right tires. Your dealer
can also provide tire/wheel balancing
services to ensure smooth vehicle
operation at all speeds. Your dealer sells
and services name brand tires.
Vehicle Care
To help keep the vehicle looking like new,
vehicle care products are available from your
dealer. For information on how to clean and
protect the vehicle’s interior and exterior,
see Interior Care 0378 and
Exterior Care 0373. Wheel Alignment
Wheel alignment is critical for ensuring that
the tires deliver optimal wear and
performance.
.Signs that the alignment may need to be
adjusted include pulling, improper vehicle
handling, or unusual tire wear.
.Your dealer has the required equipment
to ensure proper wheel alignment.
Windshield
For safety, appearance, and the best
viewing, keep the windshield clean and
clear.
.Signs of damage include scratches, cracks,
and chips.
.Trained dealer technicians can inspect the
windshield and recommend proper
replacement if needed.
Wiper Blades
Wiper blades need to be cleaned and kept in
good condition to provide a clear view.
.Signs of wear include streaking, skipping
across the windshield, and worn or split
rubber.
.Trained dealer technicians can check the
wiper blades and replace them when
needed.

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
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
Service and Maintenance 395
PartGM Part NumberACDelco Part Number
Wiper Blades
IDriver Side –55 cm (21.7 in) 84578275
—
IPassenger Side –55 cm (21.7 in) 84578275
—

Chevrolet Silverado 2500 HD/3500 HD Owner Manual (GMNA-Localizing-U.
S./Canada/Mexico-14632154) - 2021 - CRC - 11/20/20
396 Service and Maintenance
Maintenance Records
After the scheduled services are performed, record the date, odometer reading, who performed the service, and the type of services performed
in the boxes provided. Retain all maintenance receipts.Date Odometer Reading Serviced By Services Performed

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
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
Technical Data 399
ApplicationCapacities
Metric English
I3500 Series Chassis Cab –Front Tank 89.0 L
23.5 gal
I3500 Series Chassis Cab –Rear Tank 151.4 L
40.0 gal
Transfer Case Fluid 2.3 L2.4 qt
Hydraulic Power Steering Fluid 2.0 L2.1 qt
Wheel Nut Torque 190Y 140 lb ft
All capacities are approximate. When adding, be sure to fill to the approximate level, as recommended in this manual. Recheck fluid level
after filling.
*Engine cooling system capacity values are based on the entire cooling system and its components.
Engine Specifications
Engine VIN CodeSpark Plug Gap
6.6L V8 (L8T) 70.95–1.10 mm (0.037–0.043 in)
Spark plug gaps are preset by the manufacturer. Re-gapping the spark plug is not recommended and can damage the spark plug.