2021 CHEVROLET COLORADO brakes

Chevrolet/GMC 2.8L Duramax Diesel Engine Supplement (GMNA-Localizing-
U.S./Canada-14465442) - 2021 - CRC - 2/3/20
Driving and Operating 13
Driving and Operating
Starting and Operating
Starting the Diesel Engine . . . . . . . . . . . . . . 13
Winter Cover . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Engine Heater . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
Fuel Operated Heater (FOH) (VanModels Only) . . . . . . . . . . . . . . . . . . . . . . . . . 19
Parking over Things That Burn . . . . . . . . . . 19
Diesel Particulate Filter
Diesel Particulate Filter . . . . . . . . . . . . . . . . . 19
Diesel Exhaust Fluid
Diesel Exhaust Fluid . . . . . . . . . . . . . . . . . . . . 22
Brakes
Exhaust Brake . . . . . . . . . . . . . . . . . . . . . . . . . . 24
Fuel
Top Tier Fuel . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
Fuel Additives . . . . . . . . . . . . . . . . . . . . . . . . . . 25
Fuel for Diesel Engines . . . . . . . . . . . . . . . . . 25
Biodiesel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
Cold Weather Operation . . . . . . . . . . . . . . . . 27
Water in Fuel . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
Running Out of Fuel . . . . . . . . . . . . . . . . . . . . 30
Fuel Filter Replacement . . . . . . . . . . . . . . . . . 30
Filling the Tank . . . . . . . . . . . . . . . . . . . . . . . . . 32
Filling a Portable Fuel Container . . . . . . . . 34
Trailer Towing
Trailer Towing . . . . . . . . . . . . . . . . . . . . . . . . . . 34
Conversions and Add-Ons
Power Take-Off (PTO) . . . . . . . . . . . . . . . . . . . 37
Starting and Operating
Starting the Diesel Engine
The diesel engine starts differently than a
gasoline engine.
Caution
If the steering wheel is turned until it
reaches the end of its travel, and is held
in that position while starting the vehicle,
damage may occur to the power steering
system and there may be loss of power
steering assist.
Move the shift lever to P (Park) or
N (Neutral). To restart the engine when the
vehicle is already moving, use
N (Neutral) only.
Caution
Do not try to shift to P (Park) if the
vehicle is moving. If you do, you could
damage the transmission. Shift to P (Park)
only when the vehicle is stopped.
Starting the Engine
1. Turn the ignition key to ON/RUN.

Chevrolet/GMC 2.8L Duramax Diesel Engine Supplement (GMNA-Localizing-
U.S./Canada-14465442) - 2021 - CRC - 2/3/20
24 Driving and Operating
limited. For the DEF warning light symbol,
seeDiesel Exhaust Fluid (DEF) Warning Light
0 10.
DEF Quality Poor
Use only DEF that is GM approved, or fluid
containing the API certified or ISO 22241
label.
DEF has an expiration date. If the system
detects poor quality, or contaminated or
diluted DEF, the DIC message will display
along with distance until vehicle speed is
limited.
The speed limitation will occur in a series of
steps with the final speed limitation being
8 km/h (5 mph) along with a flashing
warning light and chimes.
Adding fresh DEF to the system may resolve
the problem after several kilometers/miles
of driving, depending on several factors.
If the DIC message persists, see your dealer
or additional DIC messages may display.
Service DEF System
If a problem occurs with the DEF system, a
DIC message displays along with distance
until vehicle speed is limited. The speed limitation will occur in a series of
steps with the final speed limitation being
8 km/h (5 mph) along with a flashing
warning light and chimes.
In some cases, this message will clear itself,
indicating that the DEF system was able to
correct the condition. If the DIC message
persists, see your dealer or additional DIC
messages may display.
Service Emission System
If a problem occurs with the vehicle
emission system, a DIC message displays
along with distance until vehicle speed is
limited. The speed limitation will occur in a
series of steps with the final speed
limitation of 88 km/h (55 mph) and chimes.
In some cases, this message will clear itself,
indicating that the emission system was
able to correct the condition. If the DIC
message persists, see your dealer or
additional DIC messages may display.
Brakes
Exhaust Brake
The exhaust brake can be used to enhance
the vehicle brake system and reduce brake
lining wear.Downshifts may be automatically selected
to increase engine speed, which increases
the effectiveness of the exhaust brake. The
number of downshifts selected is
determined by the length of time the brakes
are applied and the rate the vehicle is
slowing. The system delivers the correct
amount of braking to assist in vehicle
control. The heavier the vehicle load, the
more active the engine exhaust brake will
be. Use of the exhaust brake will help
maintain vehicle speed when used with
cruise control. See
“Cruise Control”in the
owner’s manual.
Automatic downshifts will not occur if the
vehicle is in Range Selection Mode. See
“Manual Mode” in the owner’s manual.
The exhaust brake only activates when the
transmission torque converter is locked. This
can vary based on vehicle speed, gear,
and load.
To activate the system, press the switch on
the center stack.

Chevrolet/GMC 2.8L Duramax Diesel Engine Supplement (GMNA-Localizing-
U.S./Canada-14465442) - 2021 - CRC - 2/3/20
34 Driving and Operating
Filling a Portable Fuel Container
{Warning
Never fill a portable fuel container while
it is in the vehicle. Static electricity
discharge from the container can ignite
the fuel vapor. You or others could be
badly burned and the vehicle could be
damaged. To help avoid injury to you
and others:
.Dispense fuel only into approved
containers.
.Do not fill a container while it is
inside a vehicle, in a vehicle's trunk, in
a pickup bed, or on any surface other
than the ground.
.Bring the fill nozzle in contact with
the inside of the fill opening before
operating the nozzle. Maintain contact
until filling is complete.(Continued)
Warning (Continued)
.Keep sparks, flames, and smoking
materials away from fuel.
.Avoid using electronic devices while
pumping fuel.
Trailer Towing
When towing at high elevation on steep
uphill grades, consider the following:
Engine coolant at higher elevation will boil
at a lower temperature than at or near sea
level. If the engine is turned off immediately
after towing at high elevation on steep
uphill grades, the vehicle may show signs
similar to engine overheating. To avoid this,
let the engine run while parked (preferably
on level ground) with the transmission in
P (Park) and the parking brake applied for at
least five minutes before turning the engine
off. If the overheat warning comes on, see
Engine Overheating062. Use the following chart to determine the
maximum the trailer can weigh, based upon
your vehicle model and options.
All axles of the trailer must be equipped
with brakes adequate for the intended use.
Trailer braking equipment conforming to
Canadian Standards Association (CSA)
requirement CAN3-D313, or its equivalent, is
recommended.

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
72 Service and Maintenance
Service and Maintenance
General Information
General Information . . . . . . . . . . . . . . . . . . . . 72
Maintenance Schedule
Maintenance Schedule . . . . . . . . . . . . . . . . . . 73
Maintenance Schedule . . . . . . . . . . . . . . . . . . 77
Recommended Fluids, Lubricants, and
Parts
Recommended Fluids and Lubricants . . . 78
Maintenance Replacement Parts . . . . . . . . 79
Maintenance Records
Maintenance Records . . . . . . . . . . . . . . . . . . . 80
General Information
This maintenance section applies to vehicles
with a diesel engine. For gasoline engine
vehicles, see the maintenance schedule
section in the owner’s manual.
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,
your 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.