CHEVROLET COLORADO 2021 Duramax Diesel Supplement

Chevrolet/GMC 2.8L Duramax Diesel Engine Supplement (GMNA-Localizing-
U.S./Canada-14465442) - 2021 - CRC - 2/3/20
50 Driving and Operating
Programmable ParametersFactory SettingMinimum Value Maximum Value
Engine Speed Tap Step Menu (In Stationary Variable and Mobile) DISABLED
DISABLED ENABLED
Remote Set Switch Speed Control DISABLEDDISABLED ENABLED
Remote Throttle Speed Control DISABLEDDISABLED ENABLED
Remote Engine Start DISABLEDDISABLED ENABLED
Remote Engine Shutdown DISABLEDDISABLED ENABLED
Throttle Override ENABLEDDISABLED ENABLED
Throttle Override Timer 10 Minutes10 Minutes 13 Minutes
Driver Door Status Usage ENABLEDDISABLED ENABLED
Remote PTO In Cab Control DISABLEDDISABLED ENABLED
If the PTO factory preset parameters do not
match the settings described above, then
they may have already been altered in order
to satisfy the requirements of the installed
PTO system and body equipment.
The following PTO settings are also offered
via the vehicle customization screens, which
can be enabled by your service technician.
These include the following parameters:
.PTO Standby rpm
.PTO Set 1 Speed
.PTO Set 2 Speed
.Tap Step Speed
.PTO Engine Run Timer
Driver Information Center (DIC) Warning
Messages
If the PTO indicator light does not remain
on, it indicates that not all PTO enabling
conditions have been met. One or more of the following DIC messages may display if
the PTO will not engage and the appropriate
action must be taken.
.PTO: SHIFT TO PARK (P) (Stationary
mode only)
.PTO: SET PARK BRAKE (Stationary
mode only)
.PTO: PRESS & RELEASE BRAKE (Mobile
mode only)
.PTO: RELEASE BRAKE TO ENGAGE PTO

Chevrolet/GMC 2.8L Duramax Diesel Engine Supplement (GMNA-Localizing-
U.S./Canada-14465442) - 2021 - CRC - 2/3/20
Driving and Operating 51
.PTO: REDUCE VEHICLE SPEED
.PTO: REDUCE ENGINE SPEED
.PTO: DISENGAGE CRUISE CONTROL
.PTO: ACCELERATION UPON BRAKE RELEASE
.PTO: SERVICE PTO
.PTO: SHIFT TO M1, M2 OR M3 (Mobile
mode only)
.Action Required Cleaning Exhaust Filter
Continue Driving (DPF only)
.Action Required Cleaning Exhaust Filter
Must Continue Driving (DPF only)
.Exhaust Filter Cleaning Available Go to
Options Menu (DPF only)
In addition, the PTO indicator light will light
when all conditions required to engage PTO
have not been met. When enabling PTO, the
PTO indicator light will turn on, then turn
off after one second. Under normal
operating conditions, the PTO indicator light
will remain on throughout the PTO
operating cycle.
Additional in-vehicle PTO module
information can be accessed by the service
technician to aid in troubleshooting. Also see
the service manual for more information. The GM service technician can access Service
Tool information that will contain reasons
why PTO may not engage and why PTO
may unexpectedly disengage due to system
conditions.
See www.gmupfitter.com for information on
the installation of wiring and programming
for PTO aftermarket equipment.
Diesel Particulate Filter Cleaning during
PTO Operation
This feature is only available on Fleet and
Commercial vehicles. To verify that the
vehicle has this feature, see
www.gmupfitter.com to contact the GM
Upfitter Integration Group for assistance.
If equipped, this feature allows for manual
cleaning/regeneration of the Diesel
Particulate Filter (DPF) when it is unable to
clean itself. It may be necessary to perform
a manual regeneration if driving conditions
—
such as extended slow speed, stop-and-go
traffic, extended idles, short drive cycles,
or stationary PTO operation —prevent DPF
self-cleaning. Manual regeneration can only be used when
the DPF has become at least 90% full. At
100% full, it will attempt to automatically
self-clean if proper driving conditions are
met. The DPF will clean itself if the vehicle
can be driven above 50 km/h (30 mph) for
about 30 minutes.
Manual regeneration can be used during a
stationary PTO session. However it is
strongly recommended that the exhaust
filter be cleaned before continuous PTO.
If manual regeneration is operating
concurrently with PTO then the PTO system
will retain control of the engine speed. Low
PTO engine speeds will cause regeneration
to take longer. To initiate a manual DPF
regeneration, see
“Manual Regeneration of
Diesel Particulate Filter” inDiesel Particulate
Filter 019.

Chevrolet/GMC 2.8L Duramax Diesel Engine Supplement (GMNA-Localizing-
U.S./Canada-14465442) - 2021 - CRC - 2/3/20
52 Vehicle Care
Vehicle Care
General Information
Accessories and Modifications . . . . . . . . . . 52
Vehicle Checks
Engine Compartment Overview . . . . . . . . . 53
Engine Oil . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55
Engine Oil Life System . . . . . . . . . . . . . . . . . 58
Automatic Transmission Fluid . . . . . . . . . . 58
Engine Air Cleaner/Filter . . . . . . . . . . . . . . . . 58
Cooling System . . . . . . . . . . . . . . . . . . . . . . . . 60
Engine Overheating . . . . . . . . . . . . . . . . . . . . 62
Battery (4-Cylinder Pickup Only) . . . . . . . . 63
Electrical System
Engine Compartment Fuse Block . . . . . . . 64
Appearance Care
Exterior Care . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71
General Information
Accessories and Modifications
Adding non-dealer accessories or making
modifications to the vehicle can affect
vehicle performance and safety, including
such things as airbags, braking, stability,
ride and handling, emissions systems,
aerodynamics, durability, and electronic
systems like antilock brakes, traction control,
and stability control. These accessories or
modifications could even cause malfunction
or damage not covered by the vehicle
warranty.
Damage to vehicle components resulting
from modifications or the installation or use
of non-GM certified parts, including control
module or software modifications, is not
covered under the terms of the vehicle
warranty and may affect remaining
warranty coverage for affected parts.
GM Accessories are designed to complement
and function with other systems on the
vehicle. See your dealer to accessorize the
vehicle using genuine GM Accessories
installed by a dealer technician.
See the warranty manual.
Aftermarket Engine Performance
Enhancement Products and Modifications
Some aftermarket engine performance
products and modifications promise a way
to increase the horsepower and torque
levels of the vehicle's powertrain. You should
be aware that these products could have
harmful effects on the performance and life
of the engine, exhaust emission system,
transmission, and drivetrain. The engine,
transmission, and drivetrain have been
designed and built to offer industry leading
durability and performance in the most
demanding applications. Engine power
enhancement products may enable the
engine to operate at horsepower and torque
levels that could damage, create failure,
or reduce the life of the engine, engine
emission system, transmission, and
drivetrain. Damage, failure, or reduced life of
the engine, transmission, emission system,
drivetrain, or other vehicle components
caused by aftermarket engine performance
enhancement products or modifications
might not be covered under the vehicle
warranty.

Chevrolet/GMC 2.8L Duramax Diesel Engine Supplement (GMNA-Localizing-
U.S./Canada-14465442) - 2021 - CRC - 2/3/20
Vehicle Care 53
Vehicle Checks
Engine Compartment Overview
2.8L 4-Cylinder Engine Pickup Models

Chevrolet/GMC 2.8L Duramax Diesel Engine Supplement (GMNA-Localizing-
U.S./Canada-14465442) - 2021 - CRC - 2/3/20
54 Vehicle Care
1. Coolant Surge Tank and Pressure Cap
2. Engine Air Cleaner/Filter
3. Engine Oil Fill Cap
4. Engine Fan (Out of View)
5. Engine Oil Dipstick
6. Engine Compartment Fuse Block
7. Brake Fluid Reservoir
8. Windshield Washer Fluid Reservoir
9. Battery

Chevrolet/GMC 2.8L Duramax Diesel Engine Supplement (GMNA-Localizing-
U.S./Canada-14465442) - 2021 - CRC - 2/3/20
Vehicle Care 55
2.8L 4-Cylinder Engine Van Models
1. Battery
2. Coolant Surge Tank and Pressure Cap
3. Engine Fan (Out of View)
4. Engine Oil Fill Cap
5. Engine Oil Dipstick 6. Engine Air Cleaner/Filter
7. Engine Compartment Fuse Box
8. Power Steering Fluid Reservoir
9. Brake Fluid Reservoir
10. Windshield Washer Fluid Reservoir
Engine Oil
To ensure proper engine performance and
long life, careful attention must be paid to
engine oil. Following these simple, but
important steps will help protect your
investment:

Chevrolet/GMC 2.8L Duramax Diesel Engine Supplement (GMNA-Localizing-
U.S./Canada-14465442) - 2021 - CRC - 2/3/20
56 Vehicle Care
.Use engine oil approved to the proper
specification and of the proper viscosity
grade. See“Selecting the Right Engine
Oil” in this section.
.Check the engine oil level regularly and
maintain the proper oil level. See
“Checking Engine Oil” and“When to Add
Engine Oil” in this section.
.Change the engine oil at the appropriate
time. See“Engine Oil Life System” in the
owner’s manual.
.Always dispose of engine oil properly. See
“What to Do with Used Oil” in this
section.
Checking Engine Oil
Check the engine oil level regularly, every
650 km (400 mi), especially prior to a long
trip. The engine oil dipstick handle is a loop.
See Engine Compartment Overview 053 for
the location.
{Warning
The engine oil dipstick handle may be
hot; it could burn you. Use a towel or
glove to touch the dipstick handle.
If a low oil Driver Information Center (DIC)
message displays, check the oil level. Follow these guidelines:
.To get an accurate reading, park the
vehicle on level ground. Check the engine
oil level after the engine has been off for
at least two hours. Checking the engine
oil level on steep grades or too soon after
engine shutoff can result in incorrect
readings. Accuracy improves when
checking a cold engine prior to starting.
Remove the dipstick and check the level.
.If unable to wait two hours, the engine
must be off for at least 15 minutes if the
engine is warm, or at least 30 minutes if
the engine is not warm. Pull out the
dipstick, wipe it with a clean paper towel
or cloth, then push it back in all the way.
Remove it again, keeping the tip down,
and check the level.
When to Add Engine Oil
If the oil is below the cross-hatched area at
the tip of the dipstick and the engine has
been off for at least 15 minutes, add 1 L(1 qt) of the recommended oil and then
recheck the level. See
“Selecting the Right
Engine Oil” later in this section for an
explanation of what kind of oil to use. For
engine oil crankcase capacity, see Capacities
and Specifications 082.
Caution
Do not add too much oil. Oil levels above
or below the acceptable operating range
shown on the dipstick are harmful to the
engine. If the oil level is above the
operating range (i.e., the engine has so
much oil that the oil level gets above the
cross-hatched area that shows the proper
operating range), the engine could be
damaged. Drain the excess oil or limit
driving of the vehicle, and seek a service
professional to remove the excess oil.
See Engine Compartment Overview 053 for
the location of the engine oil fill cap.
Be sure to add enough oil to put the level
somewhere in the proper operating range.
Push the dipstick all the way back in when
through.

Chevrolet/GMC 2.8L Duramax Diesel Engine Supplement (GMNA-Localizing-
U.S./Canada-14465442) - 2021 - CRC - 2/3/20
Vehicle Care 57
Selecting the Right Engine Oil
Selecting the right engine oil depends on
both the proper oil specification and
viscosity grade. SeeRecommended Fluids
and Lubricants 078.
Specification
Ask for and use engine oils that meet the
dexos2 specification. Engine oils that have
been approved by GM as meeting the
dexos2 specification are marked with the
dexos2 approved logo. See
www.gmdexos.com.
Use of Substitute Engine Oils if dexos2 is
unavailable: In the event that
dexos2-approved engine oil is not available
at an oil change or for maintaining proper
oil level, you may use substitute engine oil
that meets ACEA C3 of the appropriate
viscosity grade.
Caution
Failure to use the recommended engine
oil or equivalent can result in engine
damage not covered by the vehicle
warranty.
Viscosity Grade
Use SAE 5W-30 viscosity grade engine oil.
Cold Temperature Operation: In an area of
extreme cold, where the temperature falls
below −29 °C (−20 °F), an SAE 0W-40 oil
may be used. An oil of this viscosity grade
will provide easier cold starting for the

Chevrolet/GMC 2.8L Duramax Diesel Engine Supplement (GMNA-Localizing-
U.S./Canada-14465442) - 2021 - CRC - 2/3/20
58 Vehicle Care
engine at extremely low temperatures.
When selecting an oil of the appropriate
viscosity grade, it is recommended to select
an oil of the correct specification. See
“Specification”earlier in this section.
Engine Oil Additives/Engine Oil Flushes
Do not add anything to the oil. The
recommended oils meeting the dexos2
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
The engine oil life system calculates engine
oil life based on vehicle use and displays the
CHANGE ENGINE OIL SOON message when it
is time to change the engine oil and filter.
The oil life system should be reset to 100%
only following an oil change. See
“Engine Oil
Life System” in the owner’s manual.
Automatic Transmission Fluid
When to Check and Change (2.8L
4-Cylinder Engine Pickup Models)
See“Automatic Transmission Fluid” in the
owner’s manual.
When to Check and Change (2.8L
4-Cylinder Engine Van Models)
It is not necessary to check the transmission
fluid level. A transmission fluid leak is the
only reason for fluid loss. If a leak occurs,
take the vehicle to your dealer and have it
repaired as soon as possible. There is a special procedure for checking and
changing the transmission fluid. Because this
procedure is difficult, this should be done at
your dealer. Contact your dealer for
additional information.
Change the fluid and filter at the intervals
listed in
Maintenance Schedule 073 or
Maintenance Schedule 077, and be sure to
use the fluid listed in Recommended Fluids
and Lubricants 078.
Engine Air Cleaner/Filter
2.8L 4-Cylinder Engine Pickup Models
See “Engine Air Cleaner/Filter” in the
owner’s manual.
2.8L 4-Cylinder Engine Van Models
The air cleaner/filter assembly is on the
front of the engine compartment on the
driver side of the vehicle. See Engine
Compartment Overview 053.
When to Inspect/Replace the Engine Air
Cleaner/Filter
For intervals on changing and inspecting the
engine air filter, see Maintenance Schedule
0 73 or
Maintenance Schedule 077.

Chevrolet/GMC 2.8L Duramax Diesel Engine Supplement (GMNA-Localizing-
U.S./Canada-14465442) - 2021 - CRC - 2/3/20
Vehicle Care 59
How to Inspect/Replace the Engine Air
Cleaner/Filter
Do not start the engine or have the engine
running with the engine air filter housing
open. Before removing the engine air filter,
make sure that the engine air filter housing
and nearby components are free of dirt and
debris. Remove the engine air filter. Lightly
tap and shake the engine air filter (away
from the vehicle) to release dust and dirt.
Inspect the engine air filter for damage, and
replace if damaged. Do not clean the engine
air filter or components with water or
compressed air.
1. Screws
2. Retaining Clips3. Housing Base
4. Housing Cover
5. Turbo Air Duct
To inspect and replace the filter:
1. Remove the two screws (1) and lift the air cleaner/filter housing base (3) to clear
the turbo air duct (5).
2. Unlock the two retaining clips (2) on the sides of the housing cover (4) and on the
housing base and pull the cover off.
3. Remove the air cleaner/filter from the housing base. Take care to dislodge as
little dirt as possible.
4. Clean the air cleaner/filter sealing surface and housing base.
5. Install the engine air cleaner/filter by aligning the arrow on one side of the air
cleaner/filter end cap with the arrow on
top of the housing base.
6. Reinstall the housing cover by aligning the arrow on top of the cover to the
arrow on top of the housing base, and
fasten the two retaining clips.
7. Align the two bushings under the housing base to the guide pins below on
the closure assembly and push the
housing base into place. 8. Reinstall the two screws to secure the
housing base.{Warning
If part replacement is necessary, the part
must be replaced with one of the same
part number or with an equivalent part.
Use of a replacement part without the
same fit, form, and function may result
in personal injury or damage to the
vehicle.
See Maintenance Schedule 073 or
Maintenance Schedule 077 to determine
when to replace the engine air cleaner/filter.
{Warning
Operating the engine with the air
cleaner/filter off can cause you or others
to be burned. Use caution when working
on the engine. Do not start the engine or
drive the vehicle with the air cleaner/
filter off, as flames may be present if the
engine backfires.