service interval 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
Vehicle Care 307
Engine Oil Additives/Engine Oil Flushes
Do not add anything to the oil. The
recommended oils meeting the dexos1
specification are all that is needed for good
performance and engine protection.
Engine oil system flushes are not
recommended and could cause engine
damage not covered by the vehicle
warranty.
What to Do with Used Oil
Used engine oil contains certain elements
that can be unhealthy for your skin and
could even cause cancer. Do not let used oil
stay on your skin for very long. Clean your
skin and nails with soap and water, or a
good hand cleaner. Wash or properly
dispose of clothing or rags containing used
engine oil. See the manufacturer's warnings
about the use and disposal of oil products.
Used oil can be a threat to the environment.
If you change your own oil, be sure to drain
all the oil from the filter before disposal.
Never dispose of oil by putting it in the
trash or pouring it on the ground, into
sewers, or into streams or bodies of water.
Recycle it by taking it to a place that
collects used oil.
Engine Oil Life System
When to Change Engine Oil
This vehicle has a computer system that
indicates when to change the engine oil and
filter. This is based on a combination of
factors which include engine revolutions,
engine temperature, and miles driven. Based
on driving conditions, the mileage at which
an oil change is indicated can vary
considerably. For the oil life system to work
properly, the system must be reset every
time the oil is changed.
On some vehicles, when the system has
calculated that oil life has been diminished,
a CHANGE ENGINE OIL SOON message comes
on to indicate that an oil change is
necessary. Change the oil as soon as
possible within the next 1 000 km (600 mi).
It is possible that, if driving under the best
conditions, the oil life system might indicate
that an oil change is not necessary for up to
a year. The engine oil and filter must be
changed at least once a year and, at this
time, the system must be reset. For vehicles
without the CHANGE ENGINE OIL SOON
message, an oil change is needed when the
REMAINING OIL LIFE percentage is near 0%.
Your dealer has trained service people whowill perform this work and reset the system.
It is also important to check the oil regularly
over the course of an oil drain interval and
keep it at the proper level.
If the system is ever reset accidentally, the
oil must be changed at 5 000 km (3,000 mi)
since the last oil change. Remember to reset
the oil life system whenever the oil is
changed.
How to Reset the Engine Oil Life System
Reset the system whenever the engine oil is
changed so that the system can calculate
the next engine oil change. Always reset the
engine oil life to 100% after every oil
change. It will not reset itself. To reset the
engine oil life system:
1. Display the oil life percentage on the DIC. See Driver Information Center (DIC)
(Base Level) 0119 or
Driver Information Center (DIC) (Midlevel
and Uplevel) 0120.
2. Press the thumbwheel on the steering wheel, or the trip odometer reset stem if
the vehicle does not have DIC controls,
for several seconds. When the
confirmation message displays, select
YES. The oil life will change to 100%.

Chevrolet Silverado 2500 HD/3500 HD Owner Manual (GMNA-Localizing-U.
S./Canada/Mexico-14632154) - 2021 - CRC - 11/20/20
308 Vehicle Care
The oil life system can also be reset as
follows:1. Display the oil life percentage on the DIC. See Driver Information Center (DIC)
(Base Level) 0119 or
Driver Information Center (DIC) (Midlevel
and Uplevel) 0120.
2. Fully press the accelerator pedal slowly three times within five seconds.
3. If the display changes to 100%, the system is reset.
If the vehicle has a CHANGE ENGINE OIL
SOON message and it comes back on when
the vehicle is started and/or the oil
life percentage is near 0%, the engine oil
life system has not been reset. Repeat the
procedure.
Automatic Transmission Fluid
When to Check and Change Automatic
Transmission Fluid
It is usually not necessary to check the
transmission fluid level. The only reason for
fluid loss is a transmission leak or
overheated transmission. This vehicle is not
equipped with a transmission fluid level
dipstick. There is a special procedure for
checking and changing the transmission fluid in these vehicles. Because this procedure is
difficult, this should be done at the dealer.
Contact the dealer for additional information
or the procedure can be found in the service
manual. See
Publication Ordering
Information 0408.
Caution
Use of the incorrect automatic
transmission fluid may damage the
vehicle, and the damage may not be
covered by the vehicle warranty. Always
use the correct automatic transmission
fluid. See Recommended Fluids and
Lubricants 0393.
Change the fluid and filter at the scheduled
maintenance intervals listed in Maintenance
Schedule 0384. Be sure to use the
transmission fluid listed in Recommended
Fluids and Lubricants 0393.
Engine Air Filter Life System
If equipped, this feature provides the engine
air filter’s remaining life and best timing for
a change. The timing to change an engine
air filter depends on driving and
environmental conditions.
When to Change the Engine Air Filter
When the Driver Information Center (DIC)
displays a message to replace the engine air
filter at the next oil change, follow this
timing.
When the DIC displays a message to replace
the engine air filter soon, replace the engine
air filter at the earliest convenience.
The system must be reset after the engine
air filter is changed.
If the DIC displays a message to check the
engine air filter system, see your dealer.
How to Reset the Engine Air Filter Life
System
To reset:
1. Place the vehicle in P (Park).
2. Display the Air Filter Life on the DIC. See Driver Information Center (DIC) (Base
Level) 0119 or
Driver Information Center (DIC) (Midlevel
and Uplevel) 0120.
3. Press
Ton the steering wheel, or press
the trip odometer reset stem if the
vehicle does not have DIC controls, to
move to the Reset/Disable display area.

Chevrolet Silverado 2500 HD/3500 HD Owner Manual (GMNA-Localizing-U.
S./Canada/Mexico-14632154) - 2021 - CRC - 11/20/20
Vehicle Care 337
Warning (Continued)
.Worn or old tires can cause a
crash. If the tread is badly worn,
replace them.
.Replace any tires that have been
damaged by impacts with
potholes, curbs, etc.
.Improperly repaired tires can cause
a crash. Only the dealer or an
authorized tire service center
should repair, replace, dismount,
and mount the tires.
.Do not spin the tires in excess of
56 km/h (35 mph) on slippery
surfaces such as snow, mud, ice,
etc. Excessive spinning may cause
the tires to explode.
All-Season Tires
This vehicle may come with all-season tires.
These tires are designed to provide good
overall performance on most road surfaces
and weather conditions. Original equipment
tires designed to GM's specific tire
performance criteria have a TPC specification
code molded onto the sidewall. Originalequipment all-season tires can be identified
by the last two characters of this TPC code,
which will be
“MS.”
Consider installing winter tires on the
vehicle if frequent driving on snow or
ice-covered roads is expected. All-season tires
provide adequate performance for most
winter driving conditions, but they may not
offer the same level of traction or
performance as winter tires on snow or
ice-covered roads. See Winter Tires0337.
Winter Tires
This vehicle was not originally equipped
with winter tires. Winter tires are designed
for increased traction on snow and
ice-covered roads. Consider installing winter
tires on the vehicle if frequent driving on ice
or snow covered roads is expected. See your
dealer for details regarding winter tire
availability and proper tire selection. Also,
see Buying New Tires 0351.
With winter tires, there may be decreased
dry road traction, increased road noise, and
shorter tread life. After changing to winter
tires, be alert for changes in vehicle
handling and braking.
If using winter tires:
.Use tires of the same brand and tread
type on all four wheel positions.
.Use only radial ply tires of the same size,
load range, and speed rating as the
original equipment tires.
Winter tires with the same speed rating as
the original equipment tires may not be
available for H, V, W, Y, and ZR speed rated
tires. If winter tires with a lower speed
rating are chosen, never exceed the tire's
maximum speed capability.
All-Terrain Tires
This vehicle may have all-terrain or
mud-terrain tires. These tires provide good
performance on most road surfaces, weather
conditions, and for off-road driving. See
Off-Road Driving 0211.
The tread pattern on these tires may wear
more unevenly than other tires. Consider
rotating the tires more frequently than at
12 000 km (7,500 mi) intervals if irregular
wear is noted when the tires are inspected.
See Tire Inspection 0348.

Chevrolet Silverado 2500 HD/3500 HD Owner Manual (GMNA-Localizing-U.
S./Canada/Mexico-14632154) - 2021 - CRC - 11/20/20
Service and Maintenance 383
Service and Maintenance
General Information
General Information . . . . . . . . . . . . . . . . . . . 383
Maintenance Schedule
Maintenance Schedule . . . . . . . . . . . . . . . . 384
Special Application Services
Special Application Services . . . . . . . . . . . 390
Additional Maintenance and Care
Additional Maintenance and Care . . . . . 390
Recommended Fluids, Lubricants, and
Parts
Recommended Fluids andLubricants . . . . . . . . . . . . . . . . . . . . . . . . . . . 393
Maintenance Replacement Parts . . . . . . 394
Maintenance Records
Maintenance Records . . . . . . . . . . . . . . . . . 396
General Information
This maintenance section applies to vehicles
with a gasoline engine. For diesel engine
vehicles, see "Maintenance Schedule" in the
Duramax diesel supplement.
Your vehicle is an important investment.
This section describes the required
maintenance for the vehicle. Follow this
schedule to help protect against major
repair expenses resulting from neglect or
inadequate maintenance. It may also help to
maintain the value of the vehicle if it is
sold. It is the responsibility of the owner to
have all required maintenance performed.
Your dealer has trained technicians who can
perform required maintenance using genuine
replacement parts. They have up-to-date
tools and equipment for fast and accurate
diagnostics. Many dealers have extended
evening and Saturday hours, courtesy
transportation, and online scheduling to
assist with service needs.
Your dealer recognizes the importance of
providing competitively priced maintenance
and repair services. With trained technicians,
the dealer is the place for routine maintenance such as oil changes and tire
rotations and additional maintenance items
like tires, brakes, batteries, and wiper blades.
Caution
Damage caused by improper maintenance
can lead to costly repairs and may not be
covered by the vehicle warranty.
Maintenance intervals, checks,
inspections, recommended fluids, and
lubricants are important to keep the
vehicle in good working condition.
Do not have chemical flushes that are not
approved by GM performed on the
vehicle. The use of flushes, solvents,
cleaners, or lubricants that are not
approved by GM could damage the
vehicle, requiring expensive repairs that
are not covered by the vehicle warranty.
The Tire Rotation and Required Services are
the responsibility of the vehicle owner. It is
recommended to have your dealer perform
these services every 12 000 km/7,500 mi.
Proper vehicle maintenance helps to keep
the vehicle in good working condition,
improves fuel economy, and reduces vehicle
emissions.