brake fluid CHEVROLET LOW CAB FORWARD 2020 Owner's Manual

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
Introduction 9
1. Air Flow Direction ControlLever. See Air Vents0124.
2. Combination Light Control Switch. See Exterior Lamp
Controls 080.
Cruise Control Set Switch/
Resume Switch. See Cruise
Control 0214.
3. Windshield Wiper and Windshield Washer Switch.
See Windshield Wiper/Washer
0 54.
Exhaust Brake Switch. See
Exhaust Brake 0213.
4. Heater and Manual Air Conditioner. See Climate
Control Systems 0121.
5. Radio with CD/USB/Bluetooth. See AM-FM Radio 085.
6. Small Article Storage Pocket. See Instrument Panel Storage
0 43.
7. Windshield Washer Fluid Tank. See Washer Fluid 0252.
8. Glove Compartment. See Glove Box 043. 9. Relay Box. See
Electrical
System Overload 0277.
10. Cupholders 044.
11. Hook. See Shopping Bag
Hooks 045.
12. Card Holder. See Instrument
Panel Storage 043.
13. Accessory Power Outlet. See Power Outlets 055.
14. Accessory Power Outlet. See Power Outlets 055.

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
52 Instruments and Controls
Instruments and
Controls
Controls
Steering Wheel Adjustment . . . . 53
Horn . . . . . . . . . . . . . . . . . . . . . . . . . . . 53
Windshield Wiper/Washer . . . . . . 54
Power Outlets . . . . . . . . . . . . . . . . . 55
Warning Lights, Gauges, and
Indicators
Warning Lights, Gauges, andIndicators . . . . . . . . . . . . . . . . . . . . 56
Instrument Cluster . . . . . . . . . . . . . 57
Speedometer . . . . . . . . . . . . . . . . . . 58
Odometer . . . . . . . . . . . . . . . . . . . . . . 58
Trip Odometer . . . . . . . . . . . . . . . . . 58
Tachometer . . . . . . . . . . . . . . . . . . . . 59
Fuel Gauge . . . . . . . . . . . . . . . . . . . . 59
Engine Coolant Temperature Gauge . . . . . . . . . . . . . . . . . . . . . . . . 60
Diesel Exhaust Fluid (DEF) Gauge . . . . . . . . . . . . . . . . . . . . . . . . 60
Seat Belt Reminders . . . . . . . . . . . 60
Battery Warning Light . . . . . . . . . . 61
Malfunction Indicator Lamp (Check Engine Light) . . . . . . . . . 61
Service Vehicle Soon Light . . . . 62 Brake System Warning Light
(Parking Brake Light) . . . . . . . . . 62
Antilock Brake System (ABS) Warning Light . . . . . . . . . . . . . . . . 64
Exhaust Brake Light . . . . . . . . . . . 65
Service Transmission Warning
Light . . . . . . . . . . . . . . . . . . . . . . . . . 65
Automatic Transmission Fluid Temperature Warning Light . . . 66
Overdrive Off Light . . . . . . . . . . . . . 66
Wait-to-Start Light . . . . . . . . . . . . . 67
Engine Oil Pressure Light . . . . . . 67
Engine Oil Level Indicator Light . . . . . . . . . . . . . . . . . . . . . . . . . 67
Diesel Exhaust Fluid (DEF) Warning Light . . . . . . . . . . . . . . . . 68
Engine Shutdown Warning Light . . . . . . . . . . . . . . . . . . . . . . . . . 68
Idle Shutdown Light . . . . . . . . . . . . 68
Reduced Engine Power Light . . . . . . . . . . . . . . . . . . . . . . . . . 69
High-Beam On Light . . . . . . . . . . . 69
Daytime Running Lamps (DRL) Indicator Light . . . . . . . . . . . . . . . . 69
Cruise Control Light . . . . . . . . . . . 70
Information Displays
Driver Information Center (DIC) . . . . . . . . . . . . . . . . . 70
Vehicle Messages
Vehicle Messages . . . . . . . . . . . . . 74
Warning Buzzers . . . . . . . . . . . . . . 79

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
62 Instruments and Controls
If this light comes on intermittently
or continuously while driving,
service is required. Even if the
vehicle is drivable and does not
require towing, see your dealer as
soon as possible. Continued driving
without having the system serviced
could cause damage to the
emission control system. It could
also affect fuel economy and
drivability.
Service Vehicle Soon
Light
This light comes on briefly when the
engine control switch is in the ON
position, but the engine is not
running, as a check to show the
light is working. It should go out
when the engine is started.If the light stays on, or comes on
while driving, the vehicle control
system may be malfunctioning. Take
the vehicle to your dealer for service
as soon as possible.
Brake System Warning
Light (Parking Brake
Light)
This light should come on briefly
when the engine control switch is
turned to the ON position, and then
should go out after the engine is
started.
Brake System Warning Light
If the light remains on after engine
start up or comes on during
operation of the vehicle, it means
that there is something wrong with
part of the brake system.The brake system warning light
comes on while the engine is
running (after startup) in the
following situations:
.
Drop in the level of brake fluid
(due to brake lining wear or fluid
leakage).
. Abnormality in the charging
system (such as an alternator
malfunction or loose or split
fan belt).
. Abnormality in the anti-lock
brake system (ABS) and
Electronic Braking force
Distribution (EBD) functions.
(The ABS warning light and
brake system warning light will
illuminate at the same time.) See
Antilock Brake System (ABS)
Warning Light 064.
To serve as a reminder, the light
should stay on when the parking
brake is not fully released, and the
engine control switch is on. Have
the system repaired if the light does
not come on when it should. If this

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 63
warning light does not go away,
brake inspection and maintenance
should be performed.
Check and Corrective Action
1. Check to see that the parkingbrake has been fully released.
If it has, check the following:
2. Turn on the exhaust brake to help slow the vehicle.
3. Pull off the road and stop carefully. Remember that
stopping distances may be
longer, the pedal may be
harder to push, and the pedal
may go down farther than
normal.
4. Check the brake fluid reservoir on the left side of the
instrument panel. If low, add
fluid as needed.
5. If the brake fluid is not low: Try out the brakes by starting and
stopping on the shoulder of the
road, then either drive
cautiously at a safe speed to
the nearest dealer for repair,
if you judge driving to be safe; or have the vehicle towed to
the nearest dealer for repair.
Continued driving without the
necessary repairs could be
dangerous.
If this warning light stays on, see
your dealer.
The regular braking system is a split
system designed so that one part
will provide some braking if there is
a loss of hydraulic pressure in the
other part of the system.
{Warning
If this warning light comes on
while the engine is running,
immediately stop the vehicle at a
safe place well clear of traffic and
contact your dealer for inspection.
When the brake system warning
light is illuminated, brake
effectiveness may be decreased.
When this happens, strongly
press the brake pedal.
See Brakes 0253.
Parking Brake Light
This indicator light comes on when
the parking brake lever is pulled
with the engine control switch on.
This light also stays on when the
parking brake is not fully released
and the engine control switch is on.
If this warning light stays on, see
your dealer.
The illumination of the parking brake
light does not necessarily ensure
firm application of the parking brake.
The parking brake lever must be
sufficiently pulled up and locked.
Be careful not to drive the vehicle
with the parking brake lever still
pulled up.

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
64 Instruments and Controls
Brake Low Vacuum Warning
Light
This light should come on briefly
when the engine control switch is
turned to the ON position, and then
should go out after the engine is
started. If the light does not come
on when the engine control switch is
turned to ON, it could indicate a
burned out bulb or a blown fuse.
Have the system repaired if the light
does not come on during this check.
The warning light and buzzer will
come on simultaneously when the
brake booster’s vacuum or pressure
becomes insufficient either during
driving or when the engine control
switch is in the ON position, or when
there is an abnormality in the
charging system, such as an
alternator malfunction or loosening
or splitting of the fan belt or whenever the hydraulic brake
booster (HBB) becomes faulty. The
warning buzzer will stop sounding
when the parking brake is engaged.
On 4500HD and 4500XD, the brake
low vacuum warning light and
warning buzzer should come on to
indicate low vacuum reserve for
brake power assist. At the same
time, the Back up Electric Vacuum
Pump operates.
(5500HD, 5500XD models) When
the HBB pressure is low, and/or the
HBB fluid (Dexron
–VI) level is low,
the light and warning buzzer should
come on. Do not use brake fluid in
the brake booster reservoir. Use
only Dexron –VI ATF.
If this happens while driving:
. Do not pump the brakes. The
system is designed to stop the
truck with reserve power assist if
the pedal is held down. This
reserve is greatly reduced each
time you apply and release the
brakes.
. Stopping distance may be
longer. .
You may have to push much
harder on the brake pedal.
. Have the vehicle repaired before
you continue driving.
The buzzer stops when the selector
lever is shifted to the P position.
{Warning
Do not drive while the buzzer
sounds as the brakes are not
operating to their full capacity.
You and others could be seriously
injured.
Antilock Brake System
(ABS) Warning Light
This light comes on briefly when the
engine control switch is turned to
the ON position, and then should go

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 69
Reduced Engine Power
Light
This light comes on briefly when the
engine control switch is turned to
the ON position, and then should go
out after the engine is started.
If this light comes on while the
engine is running, it indicates power
is being reduced due to one or more
of the following conditions:
.Malfunction of the engine or
exhaust electronic control
system.
. DEF level is too low or empty.
If this light comes on with the
malfunction indicator lamp, see your
dealer immediately. If this light comes on with the Refill
Diesel Exhaust Fluid (DEF) warning
light and the DEF warning light, refill
DEF as soon as possible.
See
“Refill Diesel Exhaust Fluid
(DEF) Warning Light” underDriver
Information Center (DIC) 070. See
Malfunction Indicator Lamp (Check
Engine Light) 061 and
Diesel Exhaust Fluid (DEF) Warning
Light 068.
High-Beam On Light
This light comes on when the
high-beam headlamps are in use or
the headlamps are cycled between
high and low beams (passing
signal).
See Headlamp High/Low-Beam
Changer 081.
Daytime Running Lamps
(DRL) Indicator Light
This light comes on when the DRL
are on. If the vehicle is started
during the daytime with the lighting
switch off and the parking brake
released, the low beam headlamps
will come on at a reduced
brightness. The light will go out
when the lighting switch is
turned on.
See Exterior Lamp Controls 080.

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 79
Hour Meter
HOUR METER
This message and light indicate how
many hours the engine has been
run. The figure(s) on the left side of
the decimal point indicate hours
while the figure on the right side
indicates 1/10 of an hour.
Warning Buzzers
A warning buzzer may not sound if
there is a problem with the buzzer
system. If this occurs, the system
needs to be inspected. See your
dealer.
A warning buzzer sounds under the
following conditions:
.Driver seat belt not buckled —
continuous beep. See Seat Belt
Reminders 060.
. Brake booster —continuous
beep. See Brake System
Warning Light (Parking Brake
Light) 062.
. Engine overheat —
continuous beep .
Parking brake on —
continuous beep
. Low engine coolant —beep
. Engine alarm and automatic
shutdown —beep
. Diesel particulate filter (DPF)
switch regeneration —three
short beeps or three long beeps
. Selective catalytic reduction
(SCR) system —one short
beep, three short beeps, nine
quick beeps, continuous beep
See Diesel Exhaust Fluid 0180 and
Engine Alarm and Automatic
Shutdown 0164.

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
128 Driving and Operating
Driving and
Operating
Driving Information
Driver Behavior . . . . . . . . . . . . . . . 129
Driving for Better FuelEconomy . . . . . . . . . . . . . . . . . . . . 129
Distracted Driving . . . . . . . . . . . . 130
Control of a Vehicle . . . . . . . . . . . 130
Braking . . . . . . . . . . . . . . . . . . . . . . . 134
Steering . . . . . . . . . . . . . . . . . . . . . . 140
Driving on Wet Roads . . . . . . . . 140
Hill and Mountain Roads . . . . . 141
Winter Driving . . . . . . . . . . . . . . . . 142
If the Vehicle Is Stuck . . . . . . . . 144
Emergencies (Troubleshooting) . . . . . . . . . . . 145
Emergencies (Disabled Vehicle) . . . . . . . . . . . . . . . . . . . . . 155
Starting and Operating
New Vehicle Break-In . . . . . . . . . 156
Pedals . . . . . . . . . . . . . . . . . . . . . . . . 157
Ignition Positions . . . . . . . . . . . . . 157
Starting and Stopping theVehicle . . . . . . . . . . . . . . . . . . . . . . 159
Operating Temperature . . . . . . . 162
Winter Cover . . . . . . . . . . . . . . . . . 163 Engine Heater . . . . . . . . . . . . . . . . 163
Engine Alarm and Automatic
Shutdown . . . . . . . . . . . . . . . . . . . 164
Idle Shutdown . . . . . . . . . . . . . . . . 164
High Idle System . . . . . . . . . . . . . 165
Engine Checks Before Operating . . . . . . . . . . . . . . . . . . . 166
Parking over Things That Burn . . . . . . . . . . . . . . . . . . . 167
Engine Exhaust
Engine Exhaust . . . . . . . . . . . . . . 168
Running the Vehicle WhileParked . . . . . . . . . . . . . . . . . . . . . . 170
Diesel Particulate Filter
Diesel Particulate Filter . . . . . . . 171
Diesel Exhaust Fluid
Diesel Exhaust Fluid . . . . . . . . . . 180
Automatic Transmission
Automatic Transmission . . . . . . 196
Selector Lever . . . . . . . . . . . . . . . . 205
Overdrive Off . . . . . . . . . . . . . . . . . 206
Brakes
Antilock BrakeSystem (ABS) . . . . . . . . . . . . . . . 207
Parking Brake . . . . . . . . . . . . . . . . 211
Exhaust Brake . . . . . . . . . . . . . . . . 213
Cruise Control
Cruise Control . . . . . . . . . . . . . . . . 214
Fuel
Fuel for Diesel Engines . . . . . . . 218
Biodiesel . . . . . . . . . . . . . . . . . . . . . 219
Cold Weather Operation . . . . . . 221
Water in Fuel . . . . . . . . . . . . . . . . . 221
Running Out of Fuel . . . . . . . . . . 224
Filling the Tank . . . . . . . . . . . . . . . 225
Conversions and Add-Ons
Add-On Electrical Equipment . . . . . . . . . . . . . . . . . . 227
Power Take-Off (PTO) . . . . . . . . 227

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
138 Driving and Operating
2. To move the selector lever to"P" (Park), hold in the button
on the lever and push the lever
all the way toward the front of
your vehicle.
3. Turn the key to "LOCK".
4. Remove the key and take it with you.
5. Before you leave the driver's seat, be sure the vehicle is not
moving, or check that your
vehicle is in Park by trying to
pull the selector lever out of "P"
(Park) by pulling the selector
lever toward you without
pushing the button. If you can
do this, it means that the
selector lever was not fully
locked into "P" (Park).
Do Not Touch the Selector Lever
While the Vehicle is Stationary
with the Engine Idling
Do not touch the selector lever while
the vehicle is stationary with the
engine idling. If you touch the
selector lever at this time, a gear
could be selected and the vehicle
could move even with the parking brake applied. The risk of knocking
against the selector lever and
causing a crash is particularly great
when you move in or out of
your seat.
Driving Down a Long Slope
When driving down a long slope,
use the exhaust brake together with
the foot brake. Using the exhaust
brake and low-gears reduces the
work load on the foot brakes and
yields greater braking force. Even
so, use the foot brakes
appropriately to prevent the engine
over-revving.
Frequent use of the foot brakes can
cause vapor lock and brake fade,
resulting in reduced brake
effectiveness.
Brake Fade :
Frequent use of the
brakes can cause the brakes to
overheat so that the frictional force
of the brake linings decreases and
the brakes become less effective
than normal. This phenomenon is
called brake fade. Vapor Lock :
If the brakes overheat
due to frequent use, the heat can
cause the brake fluid to boil so that
air bubbles are created in the brake
fluid. Pressing the brake pedal
simply compresses the air bubbles;
pressure is not transmitted to the
wheel cylinders, so the brakes'
effectiveness sharply deteriorates.
This phenomenon is called
vapor lock.
Even so, you should be very careful
when using engine braking in a low
gear because the engine is likely to
over-rev. See Exhaust Brake 0213
and
Selector Lever 0205.
Do not adjust the exhaust brake
valve.
The engine should never be allowed
to exceed the governed speed.
Supplement the exhaust brake with
vehicle service brakes intermittently
and/or shift to higher transmission
gear to prevent engine overspeed.
A rule of thumb for gear selection is
that the vehicle should be driven
down a grade in the same gear that
would be used to climb that grade.