CHEVROLET COLORADO 2021 Duramax Diesel Supplement

C
M
Y
CM
MY
CY
CMY
K
21_MUL_2.8L_Duramax_Diesel_Engline_Supplement__COV_en_US_84267010A_2020F\
EB14.ai 1 2/12/2020 1:52:47 PM 21_MUL_2.8L_Duramax_Diesel_Engline_Supplement__COV_en_US_84267010A_2020F\
EB14.ai 1 2/12/2020 1:52:47 PM

Chevrolet/GMC 2.8L Duramax Diesel Engine Supplement (GMNA-Localizing-
U.S./Canada-14465442) - 2021 - CRC - 2/3/20
Contents
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Instruments and Controls . . . . . . . . . . . . . . . . . 3
Driving and Operating . . . . . . . . . . . . . . . . . . . 13
Vehicle Care . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52
Service and Maintenance . . . . . . . . . . . . . . . . 72
Technical Data . . . . . . . . . . . . . . . . . . . . . . . . . . . 81
Index . . . . . . . . . . . . . . . . . . . . . . . . . . . 85
Introduction
The names, logos, emblems, slogans, vehicle
model names, and vehicle body designs
appearing in this manual including, but not
limited to, GM, the GM logo, CHEVROLET,
GMC, the CHEVROLET and GMC Truck
Emblems, COLORADO, CANYON, and
Duramax are trademarks and/or service
marks of General Motors LLC, its
subsidiaries, affiliates, or licensors.
For vehicles first sold in Canada, substitute
the name“General Motors of Canada
Company” for GMC and Chevrolet Motor
Division wherever they appear in this
manual.
This manual describes features that may or
may not be on the vehicle because of
optional equipment that was not purchased
on the vehicle, model variants, country
specifications, features/applications that may
not be available in your region, or changes
subsequent to the printing of this owner’s
manual.
Refer to the purchase documentation
relating to your specific vehicle to confirm
the features. This manual contains information that
pertains to the operation of the diesel
engine. It also contains the Diesel
Maintenance Schedule. The sections in this
manual correspond to the sections in the
owner’s manual. This manual, along with
the owner’s manual, will assist you in the
proper use and maintenance of the vehicle.
Keep this manual in the vehicle for quick
reference.
Canadian Vehicle Owners
A French language manual can be obtained
from your dealer, at www.helminc.com,
or from:
Propriétaires Canadiens
On peut obtenir un exemplaire de ce guide
en français auprès du concessionnaire ou à
l'adresse suivante:
Helm, Incorporated
Attention: Customer Service
47911 Halyard Drive
Plymouth, MI 48170
USA
Litho in U.S.A.
Part No. 84267010 A First Printing©2020 General Motors LLC. All Rights Reserved.

Chevrolet/GMC 2.8L Duramax Diesel Engine Supplement (GMNA-Localizing-
U.S./Canada-14465442) - 2021 - CRC - 2/3/20
2 Introduction
Using this Supplement
This supplement contains information
specific to the unique components of the
vehicle. It does not explain everything you
need to know about the vehicle. Read this
supplement along with the owner’s manual
to learn about the vehicle's features and
controls.
Index
A good place to look for what you need is
the Index in the back of this supplement.
It is an alphabetical list of what is in the
supplement, and the page number where
you will find it.

Chevrolet/GMC 2.8L Duramax Diesel Engine Supplement (GMNA-Localizing-
U.S./Canada-14465442) - 2021 - CRC - 2/3/20
Instruments and Controls 3
Instruments and Controls
Warning Lights, Gauges, and Indicators
Instrument Cluster . . . . . . . . . . . . . . . . . . . . . . . 4
Fuel Gauge . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Engine Oil Pressure Gauge . . . . . . . . . . . . . . . 8
Malfunction Indicator Lamp (Check EngineLight) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Wait-to-Start Light . . . . . . . . . . . . . . . . . . . . . . 10
Diesel Exhaust Fluid (DEF) Warning Light . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Power Take-Off Light (Chassis Cab Only) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Information Displays
Driver Information Center (DIC) . . . . . . . . . 10
Vehicle Personalization
Vehicle Personalization (Van Models) . . . . 11
Vehicle Personalization (PickupModels) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

Chevrolet/GMC 2.8L Duramax Diesel Engine Supplement (GMNA-Localizing-
U.S./Canada-14465442) - 2021 - CRC - 2/3/20
4 Instruments and Controls
Warning Lights, Gauges, and Indicators
Instrument Cluster
English Base Level 4-Cylinder Pickup Shown, Metric Similar

Chevrolet/GMC 2.8L Duramax Diesel Engine Supplement (GMNA-Localizing-
U.S./Canada-14465442) - 2021 - CRC - 2/3/20
Instruments and Controls 5
English Uplevel 4-Cylinder Pickup Shown, Metric Similar

Chevrolet/GMC 2.8L Duramax Diesel Engine Supplement (GMNA-Localizing-
U.S./Canada-14465442) - 2021 - CRC - 2/3/20
6 Instruments and Controls
English Van Shown, Metric Similar

Chevrolet/GMC 2.8L Duramax Diesel Engine Supplement (GMNA-Localizing-
U.S./Canada-14465442) - 2021 - CRC - 2/3/20
Instruments and Controls 7
See the owner’s manual for warning lights
and gauges not listed in this supplement.
Fuel Gauge
Metric Base Level 4-Cylinder Pickup Shown,Uplevel Similar
English Base Level 4-Cylinder Pickup Shown, Uplevel Similar
Metric Van Models
English Van Models
When the ignition is on, the fuel gauge
shows approximately how much fuel the
vehicle has left in the tank. The gauge will
first indicate E (Empty) before the vehicle is
out of fuel, but the vehicle's fuel tank
should be filled soon.
An arrow on the fuel gauge indicates the
side of the vehicle the fuel door is on.
Listed are four situations customers may
experience with the fuel gauge:
.At the gas station, the fuel pump shuts
off before the gauge reads F (Full).
.It takes a little more or less fuel to fill up
than the fuel gauge indicated. For
example, the gauge may have indicated

Chevrolet/GMC 2.8L Duramax Diesel Engine Supplement (GMNA-Localizing-
U.S./Canada-14465442) - 2021 - CRC - 2/3/20
8 Instruments and Controls
the tank was half full, but it actually took
a little more or less than half the tank's
capacity to fill the tank.
.The gauge moves a little while turning a
corner or speeding up.
.The gauge does not go back to E (Empty)
when the ignition is turned off.
None of these indicate a problem with the
fuel gauge.
For information on how to fill the fuel tank,
see Filling the Tank 032.
Engine Oil Pressure Gauge
4-Cylinder Pickup Models
See “Oil Pressure” under“Driver Information
Center (DIC)” in the owner’s manual.
Metric Van Models
English Van Models
Caution
Lack of proper engine oil maintenance
can damage the engine. Driving with the
engine oil low can also damage the
engine. The repairs would not be covered
by the vehicle warranty. Check the oil
level as soon as possible. Add oil if
required, but if the oil level is within the
operating range and the oil pressure is
still low, have the vehicle serviced.
Always follow the maintenance schedule
for changing engine oil.
The engine oil pressure gauge reads in kPa
(kilopascals) or psi (pounds per square inch)
when the engine is running. Oil pressure
may vary with engine speed, outside
temperature, and oil viscosity.
If readings are outside the normal operating
range, the low oil pressure message may
display on the Driver Information Center
(DIC), or for vehicles without a DIC the oil
pressure light will come on. If the oil
pressure message or light comes on, check
the oil level immediately. Do not operate
the engine with the oil pressure warning
light on or an ENGINE OIL LOW ADD OIL
message displayed.

Chevrolet/GMC 2.8L Duramax Diesel Engine Supplement (GMNA-Localizing-
U.S./Canada-14465442) - 2021 - CRC - 2/3/20
Instruments and Controls 9
Malfunction Indicator Lamp
(Check Engine Light)
This light is part of the vehicle’s emission
control on-board diagnostic system. If this
light is on while the engine is running, a
malfunction has been detected and the
vehicle may require service. The light should
come on to show that it is working when
the ignition is on with the engine not
running. See“Ignition Positions” in the
owner’s manual.
This light may also come on when the
system has detected a problem with the
Diesel Exhaust Fluid (DEF) management
system. See Diesel Exhaust Fluid 022.
Malfunctions are often indicated by the
system before any problem is noticeable.
Being aware of the light and seeking service
promptly when it comes on may prevent
damage.
Caution
If the vehicle is driven continually with
this light on, the emission control system
may not work as well, the fuel economy
may be lower, and the vehicle may not
run smoothly. This could lead to costly
repairs that might not be covered by the
vehicle warranty.
Caution
Modifications to the engine, transmission,
exhaust, intake, or fuel system, or the
use of replacement tires that do not
meet the original tire specifications, can
cause this light to come on. This could
lead to costly repairs not covered by the
vehicle warranty. This could also affect
the vehicle’s ability to pass an Emissions
Inspection/Maintenance test. See
Accessories and Modifications 052.
When the light is on, a malfunction has
been detected. Diagnosis and service may be
required.
Poor fuel quality can cause inefficient engine
operation and poor driveability, which may
go away once the engine is warmed up. If this occurs, change the fuel brand. It may
require at least one full tank of the proper
fuel to turn the light off. See
Fuel for Diesel
Engines 025.
If the light remains on, see your dealer.
Emissions Inspection and Maintenance
Programs
If the vehicle requires an Emissions
Inspection/Maintenance test, the test
equipment will likely connect to the
vehicle's Data Link Connector (DLC).
The DLC is under the instrument panel to
the left of the steering wheel. Connecting
devices that are not used to perform an
Emissions Inspection/Maintenance test or to
service the vehicle may affect vehicle
operation. See “Add-On Electrical Equipment”
in the owner’s manual. See your dealer if
assistance is needed.