2021 CHEVROLET COLORADO torque

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
40 Driving and Operating
5. The horn will chirp, the PTO load relaywill engage, and the engine will advance
to the PTO Standby Speed.
6. The Remote PTO Set switch may be used to select PTO Set 1 and Set 2 engine
speeds.
The accelerator pedal is disabled when
Remote PTO operation is selected.
The operator may exit the vehicle.
{Warning
If the key is in the ignition during
Remote PTO operation, the vehicle can be
shifted out of P (Park) by an
unauthorized operator. Even though PTO
will be disengaged, depending on PTO
Upfitter application, personal injury or
property damage may result from vehicle
movement. The operator must ensure
that the vehicle is secured against
unauthorized access during Remote PTO
operation.
Remote PTO operation may be ended by
pressing the brake pedal at which time the
PTO load relay disengages and the engine returns to base idle speed. The operator
may drive the vehicle after releasing the
parking brake.
Preset Enable Conditions
–Operator
Selectable In-Cab Mode (OSIM)
This requires programming with the GM
Service Tool and requires pairing OSIM
stationary preset with OSIM mobile mode.
If OSIM pairing has been configured, initiate
OSIM preset operation:
1. With the engine running, shift the vehicle into P (Park) and release the
brake pedal, and set the parking brake.
2. Confirm cruise control is off.
3. Confirm the hood is closed.
4. Press and release the in-cab PTO switch. The PTO indicator light will blink slowly.
5. Within 10 seconds, press and release SET −on the cruise control.
6. The PTO indicator light will change to solid when the PTO load relay becomes
engaged. The engine speed will advance
to the PTO Standby Speed. Press and
release SET− on the cruise control to
select the PTO Set 1 speed. Press and
release +RES on the cruise control to
select the PTO Set 2 speed.
.The PTO load relay engages immediately
when the PTO operation is initiated by
the switch input. The transmission torque
converter is unlocked. The torque
converter will lock upon reaching stable
PTO Standby Speed (default = 900 rpm)
so maximum power is available.
.The first elevated engine speed, PTO
Standby Speed, is not intended as a
working speed but as a verification that
the system is active and ready to go to a
working speed. This speed can be
modified to a working speed with the GM
Service Tool. The upper limit for PTO
Standby Speed is 1500 rpm.
.The remote switches and relay
connections are made at the PTO Upfitter
Connector located on the chassis frame
behind the cab.
.The PTO Control setting on the Service
Tool must be programmed to Remote
PTO Mode Switch before the remote
switches can be used.
.The PTO relay is programmed to be
enabled in the factory default
configuration.

Chevrolet/GMC 2.8L Duramax Diesel Engine Supplement (GMNA-Localizing-
U.S./Canada-14465442) - 2021 - CRC - 2/3/20
42 Driving and Operating
Warning (Continued)
that the vehicle is secured against
unauthorized access during Remote PTO
operation.
The accelerator pedal is disabled when
Remote PTO operation is selected.
Remote PTO operation can be ended by
pressing the brake pedal. The PTO load relay
disengages and the engine returns to base
idle speed. The operator may drive the
vehicle after releasing the parking brake.
.The desired engine operating speed can
now be accomplished. Two versions of
engine rpm control are available, switches
or potentiometer, depending on which
one was installed.
‐ Switches –the Remote PTO Set and
Resume switches can be used to tap up
and tap down to the desired engine
speed.
‐ Potentiometer –a Remote PTO Throttle
Potentiometer can be used as a
continuous variable throttle control to
dial in the desired engine speed. Variable Enable Conditions
–OSIM
This requires programming with the GM
Service Tool and specific pairing of
stationary variable and mobile modes.
Remote operation is not available.
If OSIM pairing has been configured, initiate
OSIM stationary variable operation: 1. With the engine running, shift the vehicle into P (Park), release the brake
pedal, and set the parking brake.
2. Confirm cruise control is off.
3. Confirm the hood is closed.
4. Press and release the PTO in-cab switch. The PTO indicator light will blink slowly.
5. Within 10 seconds, press and release SET− on the cruise control. The PTO load
relay will engage and the PTO indicator
light will change to solid. The engine
speed will advance to the PTO Standby
Speed.
6. The desired operating speed may be achieved by tapping up and down with
+RES and SET− on the cruise control.
.The PTO load relay engages immediately
when the PTO operation is initiated by
the switch input. The transmission torque
converter is unlocked. The torque converter will lock upon reaching stable
PTO Standby Speed (default = 900 rpm)
so maximum power is available.
.The first elevated engine speed, PTO
Standby Speed, is not intended as a
working speed but as a verification that
the system is active and ready to go to a
working speed.
.The relay connections are made at the
PTO Upfitter Connector located on the
chassis frame behind the cab.
.The engine speeds can be adjusted
between the low of PTO Standby Speed
and the high of PTO Max Engine speed
limits. Both values can be modified from
the factory default settings with the GM
Service Tool. Based on the value chosen
for PTO Max Engine Speed, the PTO menu
in the center stack may show speeds that
are not available.
.Factory setting for the tap step is 100
rpm and the setting for ramp rate is 150
rpm/sec. The default value for tap step
can be modified via the Radio
Customization menu. The default values
for both tap step and ramp rate can be
changed with the GM Service Tool.
.The PTO load relay is enabled as the
factory default programmed setting.

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.