2020 CHEVROLET LOW CAB FORWARD service

Chevrolet Low Cab Forward 5.2L Diesel Engine 4500 HD/XD/5500 HD/XD
Owner Manual (GMNA-Localizing-U.S.-13337621) - 2020 - crc - 12/5/18
Instruments and Controls 77
Exhaust System Warning Light
EXH. SYSTEM
This light comes on when the SCR
system detects a malfunction or
incorrect DEF. SCR system will turn
on other indicator lights and reduce
engine power in progressive stages
to encourage you to have the
malfunction corrected. Continuing to
drive for too long after this light
turns on will eventually result in a
severe vehicle speed limitation.
If this light turns on, promptly have
the vehicle inspected and serviced
at your dealer. SeeDiesel Exhaust
Fluid 0180.
Refill Diesel Exhaust Fluid
(DEF) Warning Light
REFILL DEF
This message displays and a
warning light appears when the DEF
tank is almost empty. Add DEF as
soon as possible.
Engine power will be reduced and
vehicle speed will be limited when
this light is activated. Failure to
promptly refill the DEF tank will result in a severe vehicle speed
limitation. See
Diesel Exhaust Fluid
0 180.
When DIC ERROR is Displayed
ERROR
If the system has not yet been able
to access maintenance data,
ERROR is shown on the DIC.
If ERROR does not change
automatically to a distance or other
maintenance indication, have your
vehicle serviced at your dealer.
Maintenance Data Indicator
Lights
Maintenance data indicator lights
appear on the DIC when each
maintenance item is selected or
when the next change or service
interval of the item is near or has
been reached.
The distance or time shown is the
remaining or excess of them to /
from the change or service timing.
The positive distance or time shows
the remaining of that and the
negative distance or time shows the excess of that. For the items listed
below, the displayed color will
change from green to amber when
remaining distance is below
1 600 km (1,000 mi) and the screen
is selected.
These screens are also displayed
when the engine control switch
turns to the ON position after above
notification timing. The message
remains on the display until the DIC
selector is pressed once or the
vehicle is started.
The maintenance data function
indicates the distance remaining
before the next scheduled
maintenance. Scheduled
maintenance time is approaching
when the display turns from green
to amber. Have the vehicle checked
and serviced at your dealer as soon
as possible.
The vehicle needs to be maintained
more often if it is driven in severe
conditions.

Chevrolet Low Cab Forward 5.2L Diesel Engine 4500 HD/XD/5500 HD/XD
Owner Manual (GMNA-Localizing-U.S.-13337621) - 2020 - crc - 12/5/18
Infotainment System 91
If a disc could not be ejected,
contact nearest dealer for service.
Track (File) Selection
Press
yorzto select the
track (file) of your choice.
. Press
yto advance to the next
track (file).
. Press
zto return to the
beginning of the track (file) being
played. To return to the previous
track (file), press again.
Selecting the Folder
For CD (MP3/WMA):
Press 5 or 6 to select the MP3/WMA
folder.
. Press
nto advance to the next
folder.
. Press
qto return to the
previous folder.
Fast Forwarding/Fast Reversing
Press and hold
yorzto fast
forward or fast reverse the
track (file). .
Press
yfor fast forward.
. Press
zfor fast reverse. To
stop fast forward or fast reverse,
release.
Repeat Playback
For CD:
Press 1.
wis displayed.
To cancel, press 1 again.
For CD (MP3/WMA):
. Press 1 to repeat the same file
being played.
wis displayed.
To cancel, press 1 twice.
w
disappears.
. Press 1 twice to repeat the same
folder being played. After the
player has played the last file, it
starts playing the first file of the
same folder. FLD
wis
displayed.
To cancel, press 1 again. FLD
wdisappears. Random Playback
For CD:
Press 2.
vis displayed.
To cancel, press 2 again.
For CD (MP3/WMA):
. Press 2 to play all files in the
MP3/WMA disc in random order.
vis displayed.
To cancel, press 2 twice.
v
disappears.
. Press 2 twice to play the files
from the folder being played in
the MP3/WMA disc in random
order. After the player has
played the last file, it starts
playing the first file of the same
folder. FLD
vis displayed.
To cancel, press 2 twice. FLD
vdisappears.
Selecting a Music File from the
Category List
For CD (MP3/WMA): 1. Press LIST for less than one second. LIST is displayed.

Chevrolet Low Cab Forward 5.2L Diesel Engine 4500 HD/XD/5500 HD/XD
Owner Manual (GMNA-Localizing-U.S.-13337621) - 2020 - crc - 12/5/18
Infotainment System 93
If Error Appears in the Display
The following messages are
displayed (blink) according to the
status.
.LOAD: This message is
displayed right after inserting a
disc into the main unit or while
reading TOC
. READING: This message is
displayed when reading the file
format of the disc in the MP3/
WMA mode.
. CD CHECK: This message is
displayed when the disc is
stained or upside-down. This
message is displayed when a
disc reading error or a
media-dependent error occurs,
including when a blank disc is
inserted. Check the disc in the
player.
. DECK ERROR: This message is
displayed when the player
cannot operate for some reason.
Eject the disc from the audio
system. .
NO SUPPORT: This message is
displayed when the disc is in
one of the following conditions:
‐Not in
ISO9660 Level 1, 2 format
‐ Not containing MP3/WMA data
(including MP3/WMA
extension files)
‐ Containing only SKIP FILEs
If a disc cannot be ejected, please
contact nearest dealer for service.
Using the Compact Disc
System
Disc
When it is cold or when it is raining,
the car windows will fog up and
cause condensation (water drops) to
form in the vehicle compartment.
When this happens, the audio may
skip, and playback will stop.
Ventilate the vehicle compartment
and dehumidify before
resuming use.
The audio may skip due to violent
vibrations when the car is traveling
across harsh roads. Never insert foreign objects into the
disc insertion slot.
Do not insert a wet disc into the
player.
This player uses an invisible laser
beam which could cause hazardous
radiation exposure if directed
outside the player. Be sure to
operate the player correctly.
Playback may not be possible due
to recording conditions or disc
characteristics, scratches, dirt,
or deterioration.
Usable Discs
Music CDs with the following marks
can be used. CD-R and CD-RW
discs recorded according to the
CD-DA format can also be played.
.
CD-R (CD-Recordable), CD-RW
(CD-ReWritable) may not be
able to play back due to the
recording condition,
characteristics of the disc,
damage, dirt or deterioration due
to long exposure to the
environment of the vehicle
compartment. CD-R, CD-RW

Chevrolet Low Cab Forward 5.2L Diesel Engine 4500 HD/XD/5500 HD/XD
Owner Manual (GMNA-Localizing-U.S.-13337621) - 2020 - crc - 12/5/18
Climate Controls 121
Climate Controls
Climate Control Systems
Climate Control Systems . . . . . 121
Air Vents
Air Vents . . . . . . . . . . . . . . . . . . . . . 124
Maintenance
Passenger Compartment AirFilter . . . . . . . . . . . . . . . . . . . . . . . . 125
Service . . . . . . . . . . . . . . . . . . . . . . . 126
Climate Control
Systems
The heating, cooling, and ventilation
for the vehicle can be controlled
with this system.
Climate Control System w/Air
Conditioning shown, Heater Only similar
1. Outlet Selector Knob
2. Air Selector Lever
3. Temperature Control Knob
4. Air Conditioning (A/C) Switch, if equipped
5. Fan Speed Control Knob Outlet Selector Knob :
The Air
Selector Knob regulates air flow
from the upper, floor and defroster
outlets.
H: Air flows through the upper
outlets.
): Air flows through the upper and
floor outlets.
6: Air is flows through the floor
outlets.
-: Air flows through the floor
outlets, with some air coming from
the door window and windshield
outlets.
1: Air flows through the door
window and windshield outlets.
Air Selector Lever : The intake of
outside air and the circulation of
inside air is controlled by sliding this
lever right or left.
P: Use this position to ventilate
the interior of the cab. This position
should be normally selected.

Chevrolet Low Cab Forward 5.2L Diesel Engine 4500 HD/XD/5500 HD/XD
Owner Manual (GMNA-Localizing-U.S.-13337621) - 2020 - crc - 12/5/18
126 Climate Controls
Ensure that the filter is returned
securely to its original position.
Failure to observe this precaution
can lead to rattling during travel.
The vehicle must not be used with
the filter removed or incorrectly
installed. Failure to observe this
precaution can lead to air
conditioning system damage as a
result of dust, dirt and the like
entering the system.
Removing the Outside Air Filter1. Remove the filter from underthe instrument panel on the
passenger side. While pressing
in the filter lock, on both sides,
pull out the filter.
2. Use a vacuum cleaner or the like to clean dust and dirt from
its surface.
In order to avoid filter damage, hard
brushes should not be used for filter
cleaning.
Installing the Outside Air Filter
Install the filter in the reverse order
to removal.
Ensure that the filter is returned
securely to its original position.
Failure to observe this precaution
can lead to rattling during travel.
The vehicle must not be used with
the filter removed or incorrectly
installed. Failure to observe this
precaution can lead to air
conditioning system damage as a
result of dust, dirt, water, snow, and
the like entering the system.Service
The air conditioning system will not
be able to cool the cab interior
effectively if the refrigerant level is
low. Accordingly, the refrigerant
level must be topped up whenever
necessary.
Please contact your dealer
whenever refrigerant must be
added.
Operation Tips
Operating the air conditioning while
the refrigerant level is too low leads
not only to poor cooling
performance but also to air
conditioning system damage.
This vehicle uses the new
refrigerant HFC134a (R134a) in the
air conditioning system. No other
type of refrigerant can be used. In
order to protect the environment,
care must be taken to ensure that
refrigerant gas is never released
into open air. When refrigerant must
be replaced, therefore, please

Chevrolet Low Cab Forward 5.2L Diesel Engine 4500 HD/XD/5500 HD/XD
Owner Manual (GMNA-Localizing-U.S.-13337621) - 2020 - crc - 12/5/18
Climate Controls 127
contact your dealer or other service
facility equipped with a gas recovery
installation system.

Chevrolet Low Cab Forward 5.2L Diesel Engine 4500 HD/XD/5500 HD/XD
Owner Manual (GMNA-Localizing-U.S.-13337621) - 2020 - crc - 12/5/18
Driving and Operating 133
Refer toEngine Coolant 0243.
. Do not put well water, river water
or other hard water in the engine
cooling system. It would hasten
the formation of rust and scale.
. If foreign matter (insects, mud,
etc.) gets stuck in the radiator's
air passages, the cooling
system's performance will
deteriorate. Check the air
passages for clogging, and
remove any foreign matter using
water under low pressure.
Refer to Exterior Care 0307.
When Turning, the Rear
Wheels will Follow Tighter
Curves than the Front Wheels
Use the mirrors to confirm safety.
Sidewinds
If the vehicle catches a sidewind
and drifts sideways, firmly grip the
steering wheel, decelerate to a
speed that allows you to stay
completely in control, and make a directional correction. The vehicle
may catch strong sidewinds in the
following situations:
.
Emerging from a tunnel
. Driving over a bridge
. Driving on an embankment
. Driving through a cutting
. Being overtaken by a large truck
or bus
. Overtaking a large truck or bus
Flat Tire
If a blowout or flat tire occurs while
you are driving, calmly grip the
steering wheel and gradually apply
the brakes to decelerate. (Hard
braking would be dangerous
because it could cause the steering
wheel to be pulled to one side.)
Stop the vehicle in a safe place, and
change the tire.
Hard Bump Under Vehicle
If the underside of the vehicle
receives a hard bump, stop in a safe
place where the vehicle will not
obstruct traffic and check for brake fluid leakage, fuel leakage and
component damage. If any part of
the vehicle is damaged or broken,
promptly have the vehicle inspected
and repaired.
Highways
.
Speeds on highways are higher
than those on regular roads, so
there is more danger. Also, a
breakdown on a highway
represents a hazard to other
vehicles and can cause a crash.
Concentrate on safe driving.
Remember to perform daily
pre-operation inspections and
use highway driving techniques.
When performing daily
pre-operation inspections,
perform the checks shown in the
table on the left with particularly
great care.
Refer to Owner Checks and
Services 0330.
. When merging with traffic on a
highway, use the turn signal
lights to indicate your intentions
ahead of time. Speed up
sufficiently when you are in the

Chevrolet Low Cab Forward 5.2L Diesel Engine 4500 HD/XD/5500 HD/XD
Owner Manual (GMNA-Localizing-U.S.-13337621) - 2020 - crc - 12/5/18
136 Driving and Operating
The exhaust brake should be turned
on as soon as service brake
malfunction is detected. This will
slow the engine speed. With the
engine speed under control and
providing the grade conditions
permit, the transmission can be
progressively downshifted using the
exhaust brake in each gear.
Eventually the exhaust brake should
slow the vehicle to a controllable
“crawl.”Gradually pull the parking
brake lever while firmly holding on
to the steering wheel. Stop the
vehicle on the side of the road. The
vehicle should not be driven further
until corrective measures are taken.
See Exhaust Brake 0213 and
Parking Brake 0211.
Riding the Brake
{Warning
"Riding the brake" by resting your
foot on the pedal, when you do
not intend to brake, can overheat
the brakes and wear out the (Continued)
Warning (Continued)
brake linings faster. This may also
damage the brakes and will waste
fuel. It can also result in reduced
braking performance.
You and others could be seriously
injured.
Applying the Parking Brake
Except in an emergency, do not
apply the parking brake until the
vehicle has come to a complete
stop. Applying the parking brake
before the vehicle has stopped can
cause a breakdown.
Refer toParking Brake 0211.
Parking Safely on a Slope
Avoid parking your vehicle on a
slope as much as possible and
choose a level and flat place. If you
must park your vehicle on a slope,
be sure to set the parking brake
fully. Make sure that the vehicle
does not move, and block the
wheels with chocks for added safety. Also, leave the vehicle in
gear to further ensure that it will not
move. Leave the steering wheel
turned such that the vehicle will be
stopped by an obstruction (for
example, the curb) in the unlikely
event that it moves.
Stopping and Parking with the
Engine Running
{Warning
When parking with the engine
running, first come to a complete
stop, then firmly apply the parking
brake, then move the selector
lever to the "P" (Park) position.
Unless you take these steps, any
unintended pressure on the
accelerator pedal could cause a
crash.
To reduce the chance of personal
injury and/or vehicle damage due
to engine overheating, never
leave the engine idling without an
alert driver present. If the engine
(Continued)