brake fluid CHEVROLET LOW CAB FORWARD 2020 User Guide

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 151
SymptomCauseCorrective Action Reference
Not enough engine power Parking brake not fully
released
Make sure it is fully
released
-
Brake dragging
4-
Air cleaner clogged
4-
Fuel filter clogged
4-
Engine control system
faulty
4-
Common rail system
faulty
4-
Engine faulty
4-
DPF clogged
4-
Brakes not effective Drum-to-lining gap too
large
4-
Air in brake fluid
4-
Brake system failure
4-

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
152 Driving and Operating
SymptomCauseCorrective Action Reference
Uneven braking Unbalanced air pressure
in tires
Adjust to proper air
pressureSee
Wheels and
Tires 0285
Tire unevenly worn Replace tire See
Wheels and
Tires 0285
Drum brake out of
adjustment
4-
Poor wheel alignment
4-
Exhaust brake not working The electrical system is
faulty
4-
Steering wheel hard to turn Loaded too far forward Load properly -
Power steering fluid level
too low
Add fluidSee
Power
Steering Fluid
0 252
Insufficient air in front
tires Adjust to proper inflation
pressureSee
Wheels and
Tires 0285

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
162 Driving and Operating
filled before leaving the vehicle
standing for an extended
period.
Do not use starting aids in the air
intake system. Such aids can cause
immediate engine damage. See
Fuel for Diesel Engines 0218.
Stopping the Engine
When stopping the engine, take the
following steps: 1. Bring the vehicle to a complete stop.
2. Firmly apply the parking brake.
3. Move the selector lever to the P position and make sure that
the shift indicator shows P.
4. Allow the engine to idle for approximately 3 minutes.
5. Turn the engine control switch to the ACC or LOCK position.
Do not shut down the engine
immediately after driving the vehicle.
Otherwise, a seizure or other
failures may result. To prevent the battery from going
dead, turn the engine control switch
to the ACC or LOCK position after
stopping the engine. If you leave the
vehicle for an extended period of
time, place the engine control switch
in the LOCK position.
Let the engine idle for 3 minutes
before shutting off the engine. This
allows the turbocharger to slow
down while keeping the bearings
lubricated.
If the Vehicle Has Not Been Used
for a Long Period
If a diesel vehicle has been
standing for an extended period of
time, the turbocharger bearings
should be pre-lubricated prior to
starting. See your authorized dealer
for more detailed information.
Before using a vehicle that has not
been driven for a long period, check
the engine and transmission for oil
leakage, and make sure the oil is at
the required levels. If there is
insufficient oil, it will not adequately
reach and lubricate components,
and a breakdown will result.Start the engine and allow it to idle
for at least five minutes. Check for
abnormal noises.
For instructions on warming up the
engine, refer to
“Starting the Engine”
previously in this section.
If one year has passed since the
diesel exhaust fluid (DEF) in the
DEF tank was added, the DEF in
the tank should be replaced. Be
careful not to inhale the ammonia
odor when replacing the DEF. Also,
please contact your nearest dealer
about the replacement work.
Operating Temperature
Recommendations for Warming
Up the Engine
The engine is sufficiently warmed
up when the needle of the engine
coolant temperature gauge starts
to move.
Do not race the engine or quickly
accelerate before the engine has
sufficiently warmed up. Oil would
not have adequately reached and
lubricated components, and a
breakdown may result.

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
166 Driving and Operating
The cruise set indicator light will
stop flashing and the engine speed
will return to normal.
Engine Checks Before
Operating
Checks Before Operating
Allow the engine to warm up before
placing the engine under heavy load
driving. While the engine is warming
up under light load, the following
checks should be made:1. Observe the red engine oil pressure warning light. The
light should go out when the
engine is running. If it stays on,
shut the engine off and find the
cause.
2. Look at the engine coolant temperature gauge. If the
gauge reaches the H (HOT)
area, stop the engine and find
the cause of the overheating.
3. Check that the battery warning light has gone out. The light
should go off and stay off at
normal idle speeds. If the light does not go out or comes on
during normal operation, have
the charging system checked.
4. Check that the brake low vacuum warning light is out
and that the vacuum buzzer is
not sounding. It is normal for
the warning buzzer to sound
for a few seconds after the
engine starts. If the light and
buzzer remain on, do not drive
the vehicle until the cause has
been found and corrected.
5. Look at the brake system warning light. It should be out
when the parking brake is
released and the engine is
running. If it stays on, it could
mean that the brake fluid level
is low. Check the brake fluid
reservoir. This condition must
be corrected before moving the
vehicle.
{Warning
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
should overheat, as indicated by
the engine coolant temperature
gauge, immediate action is
required to correct the condition.
Continued operation of the
engine, even for a short time, may
result in a fire.
Do not engage the exhaust brake
while the engine is idling as this
may cause engine overheating.
You and others could be seriously
injured.
Avoid Unnecessary Idling of the
Diesel Engine
If the diesel engine idles too long,
the engine coolant temperature will
fall below the operating range. Low

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
180 Driving and Operating
the selectable (switch) regeneration
required warning light (red) is
displayed on the DIC.
Continued driving without
performing DPF regeneration will
cause the check engine malfunction
indicator light and reduced engine
power indicator light to come on, an
engine power reduction, and may
cause damage to the DPF filter. See
Vehicle Messages074.
The time needed to complete
regeneration differs depending on
the outside temperature.
The exhaust brake is activated
during DPF regeneration. The
exhaust brake starting to operate or
being disengaged will produce a
sound, but this does not indicate a
failure.
During regeneration, white smoke
may be temporarily produced from
the exhaust pipe. This results from
combustion of PM, it does not
indicate a failure.
Regeneration is finished earlier
immediately after driving than when
the engine is cold. The engine coolant temperature
may rise during regeneration.
DPF Regeneration during
Prolonged Idling
DPF regeneration may be initiated
automatically during prolonged
idling. If regeneration is initiated, the
regeneration in progress indicator
light (amber) comes on but this is
normal and does not indicate a
failure.
If driving is started or the PTO is
connected during DPF regeneration
by prolonged idling, the selectable
(switch) regeneration required
warning light (amber) comes on and
regeneration is suspended. Perform
Switch regeneration procedure in
order to complete the DPF
regeneration.
Prolonged idling may require more
frequent DPF regeneration.
See
Driver Information Center (DIC)
0 70.Diesel Exhaust Fluid
Diesel exhaust fluid (DEF) is used
exclusively for the selective catalytic
reduction (SCR) system. Be sure to
use only API certified DEF. When
the SCR system detects DEF level
is nearly empty or incorrect fluids
(such as water or low concentrated
DEF.) are added, the SCR system
will turn on warning and indicator
lights and reduce engine power in
progressive stages to encourage
you to have the condition corrected.
Continuing to drive for too long after
these lights come on will eventually
result in a severe vehicle speed
limitation. See Vehicle Messages
0 74
The DEF freezes below −11 °C
(12 °F). The SCR system is
equipped with a heating function
which utilizes the engine coolant, so
the engine can be started even
when DEF is frozen.

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
196 Driving and Operating
When the exhaust system warning
light comes on, promptly have the
vehicle inspected and serviced at a
dealer.
When a malfunction is detected in
the SCR system, the warning and
the indicator lights shown in the
table come on. SeeVehicle
Messages 074, Malfunction
Indicator Lamp (Check Engine
Light) 061, and Diesel Exhaust
Fluid (DEF) Warning Light 068.
When the Diesel Exhaust Fluid
(DEF) Tank is Empty
If the DEF tank is empty and
warning and indicator lights are on,
you must follow below procedure to
cancel the vehicle restriction: 1. Turn the engine control switch to the LOCK or ACC position,
and add DEF.
2. After adding DEF, turn the engine control switch to ON
position.
3. Wait until buzzer stops, warnings and indicators are
turned off. 4. If the buzzer does not stop,
return the engine control switch
back to the LOCK position and
add more DEF, and then start
over from step 2 above.
5. Restart the engine.
It may take a while until the warning
lights and indicators turn off and the
buzzer stops after turning the
engine control switch to the ON
position.
It is desirable to fill up the tank with
DEF to avoid DEF remaining level
warning indication from reappearing.
When the outside temperature is
low, refer to Adding DEF in Cold
Weather. See Driver Information
Center (DIC) 070, Brake System
Warning Light (Parking Brake Light)
0 62, Warning Buzzers 079, and
Winter Driving 0142.Automatic
Transmission
On an automatic transmission
vehicle, the driver does not use a
clutch pedal when pulling away,
changing gears, or stopping. Only
the selector lever, accelerator pedal,
and brake pedal are used.
Practice learning the characteristics
of the automatic transmission
vehicle and how to correctly operate
it. When the vehicle is stationary,
remember to keep the brake pedal
firmly pressed, and if necessary,
move the selector lever in the P or
N position and apply the parking
brake.
Creep : With the engine running
and a gear position other than P or
N selected with the selector lever,
power reaches the wheels even
when the accelerator pedal is not
pressed, causing the vehicle to tend
to move.

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 199
To start your vehicle:1. Firmly press the brake pedal. After making sure the selector
lever is placed into P or N, that
P or N is shown in the shift
indicator and that the parking
brake lever is fully pulled up,
place the engine control switch
into the ON position.
2. Start the engine and move the selector lever into D for forward
movement, or R for backward
movement while firmly pressing
the brake pedal with your
right foot.
3. Make sure that the shift indicator indicates the correct
gear (D for forward movement,
or R for backward movement),
release the parking brake,
release the brake pedal, and
then gradually press the
accelerator pedal. The vehicle
starts moving as you press the
accelerator pedal further. On a steep slope:
Make sure that the shift indicator
indicates the correct gear (D for
forward movement, or R for
backward movement), check the
area around the vehicle is clear,
release the brake pedal with your
right foot, and then slowly press the
accelerator pedal.
After you feel the vehicle start
moving, gradually release the
parking brake lever and start driving
the vehicle.
When the brake pedal is not
pressed, the shift lock system
operates and the selector lever
cannot be shifted from P to any
other position.
See
Driver Information Center (DIC)
0 70, Starting and Stopping the
Vehicle 0159, Selector Lever 0205,
and Automatic Transmission Shift
Lock Control Function Check 0264. Normal Driving
When you move the selector lever
from P into D, shifting takes place in
the automatic mode. Check that D is
displayed in the shift indicator.
If the automatic transmission fluid
temperature is too low, the
transmission may not initially make
automatic shift to the 4th, 5th, and
6th gear. This condition is normal
and will be resolved as the fluid
temperature rises.
To Accelerate
To accelerate when the accelerator
pedal is pressed further, kickdown
operates and the speed increases.
The transmission will downshift at
speeds below 88 km/h (55 MPH), to
provide greater acceleration.
Kickdown
If you press the accelerator pedal
fully while driving, in accordance
with the current speed the gear
automatically shifts down and the
engine speed rises, enabling
sufficient acceleration. This is called
kickdown.

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 201
Driving conditionsSelector lever position
Normal uphill road D (overdrive off switch ON)
Steep uphill, steep slope, mountain
road with many sharp curves 2 or 1
Long uphill road 2
Downhill driving:
Do not overuse the foot brake. This
will cause the brakes to overheat,
reducing their effectiveness. On
long downward slopes or sharp
downhill sections of road, use the
engine brake together with the foot
brakes to control the speed.
When the selector lever is in the D
position, you can drive with the
overdrive off switch ON to allow a
gentle engine brake to be applied.
Push the overdrive off switch to the
ON position at speeds below
101 km/h (63 MPH) to increase
engine braking action when
traveling downgrade. You can increase engine braking by
driving with the selector lever in the
2 position.
To apply a stronger engine brake on
sharp downhill sections, shift the
selector lever to the 1 position when
required.
See
Control of a Vehicle 0130.
Driving at Low Speeds for
Sustained Periods
Any low speed applications such as
sweeper, road marking machinery,
trash collectors, highway striping or
moving, etc. require the following
treatment to prevent the automatic
transmission fluid (ATF) from
overheating:
Select 1 position during low speed
operation under 18 km/h (11 MPH). Select 2 position during low speed
operation under 36 km/h (22 MPH).
See
Automatic Transmission Fluid
Temperature Warning Light 066.
To Stop Your Vehicle 1. To temporarily stop the vehicle, press the brake pedal firmly
while the selector lever is in D.
2. Use the parking brake as required. Press the brake pedal
firmly, and firmly apply the
parking brake.
If the vehicle is stationary for a
long time, move the selector
lever into the N or P position.
If the selector lever is kept in
D, the temperature of the
automatic transmission fluid
increases due to heat from the
torque converter.
To ensure reliable brake application,
be sure to use your right foot to
press the brake pedal.
When leaving the driver's seat,
follow the When Parking Your
Vehicle procedure.

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
204 Driving and Operating
Actions that Can Lead to a Breakdown with an Automatic Transmission
Actions that can lead to a breakdownBreakdown symptoms
Stopping the vehicle on an uphill road with the selector lever in a position
other than R, N, or P, the accelerator pedal pressed, and the brakes not
applied. The transmission fluid overheats.
Continuously pressing the accelerator pedal and brake pedal at the same
time while the vehicle is in a position other than N or P.
Placing the selector lever into any gear with the accelerator pedal pressed
and the engine speed high. The transmission gears are
overloaded.
Placing the selector lever into P before the vehicle has completely stopped. The parking mechanism will be
damaged.
Turning off the engine control switch while driving. The transmission is not properly
lubricated.
Driving with the selector lever in the N position on a long downward slope
(this is dangerous due to the lack of engine brake).

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
224 Driving and Operating
Running Out of Fuel
When the Fuel Tank is Empty
When the fuel tank is empty, air will
enter the fuel system, so refueling
alone will not be enough to restart
the engine. Use the following
methods to bleed the fuel system.
Bleeding the Fuel System
Steps for Refueling1. Follow the directions in "Parking Brake Lever" under
Parking Brake 0211. 2. Select the correct fuel (See
"Diesel Fuel Requirement and
Fuel System"). Follow any
posted safety rules. Stand to
the side, never above or
opposite the filler opening.
3. Check that the fuel cap is tight, and see to it that engine oil,
engine coolant in the reservoir,
and washer fluid, etc. are at
proper levels. Then do the
Driver Daily Checklist.
See Owner Checks and Services
0 330.
Driving your vehicle until the fuel
tank is empty may activate the
check engine malfunction indicator
light. You do not need to have your
vehicle checked. After refueling,
perform the following:
. Bleed the fuel system.
. Start, turn off and restart the
engine three or four times.
. The check engine malfunction
indicator light will be cancelled. Before Starting the Engine
1. The priming pump (1) is
located on the outboard side of
the left frame rail, in front of the
batteries. Place a container
beneath the air bleed plug (2)
to receive fuel, and then fully
loosen the plug.
2. Attach a clear hose onto the air bleed plug, direct the clear
hose into a catch pan.
3. Pump the priming pump (1) up/ down for 65 times to get most
of the air bubbles out. Note fuel
was drawn into the filter bowl at
around 40 - 50 times.