2020 CHEVROLET LOW CAB FORWARD heater

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 161
usually requires 30 seconds to
2 minutes depending on ambient
conditions. This will help reduce
white start-up smoke.
Preheating :Diesel engines are
compression ignited, which makes
them difficult to start when they are
cold because the compression
alone cannot create a temperature
high enough for fuel to ignite.
Preheating means warming the
compressed air inside the
combustion chambers to facilitate
engine starting. Be sure to start the
engine after the wait-to-start light
has gone out.
Start : Do not press the accelerator
pedal at the engine start. The
accelerator opening degree at the
engine start is electronically
controlled.
Warm-up : Do not race the engine
to speed warm-up. Cold Weather Starting
If you plan ahead for cold weather,
starting and driving your vehicle
should be no problem. The following
tips will help ensure good starting in
cold weather.
Oil gets thicker as it gets colder,
which slows down the engine
cranking speed. The diesel engine
functions by the heat of
compression (and glow plugs when
cold), rather than through the use of
spark plugs as in a gasoline engine.
So, your engine must crank faster
than a gasoline engine before it will
start.
To be sure the engine can turn fast
enough to start, use SAE 10W-40
viscosity engine oil when prevailing
temperatures drop below 0 °C
(32 °F). See the oil quality and oil
viscosity recommendations. Using
the proper viscosity oil will make
starting easier down to -23 °C
(-10 °F). When prevailing
temperatures drop below -23 °C
(-10 °F), the engine block heater
may be needed for starting. See
Engine Heater
0163. Maintenance Items to Aid Cold
Weather Starting
Since the basic principle of diesel
engine ignition is based on
compression, the diesel engine is
somewhat harder to start than a
gasoline engine when the
temperature is below freezing.
To help prevent hard starting
problems, special attention should
be given to following normal
maintenance items:
1. Neglecting to have the fuel filter and water separator
serviced can be one of the
major contributors to hard
starting. If water is permitted to
accumulate in the primary filter,
it will freeze and make starting
the engine impossible.
2. Make sure the fuel tank vent is open.
3. Always refuel at the end of a day's operation. Moisture will
condense in an empty tank;
therefore, the tank should be

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 163
The exhaust pipe becomes
extremely hot while the engine is
idling. Before warming up the
engine, make sure there is no
flammable material, such as grass,
waste paper, oil, or old tires near the
exhaust pipe.
Engine Warm-up System
During cold ambient conditions, the
automatic engine warm-up system
operates to reduce engine warm-up
time during idling.
Automatic Engine Warm-up :
When the engine is idling with the
engine coolant temperature below
62 °C (144 °F), the engine warm-up
system automatically closes the
exhaust brake and increases engine
idle speed so that the engine is
warmed more quickly. Warm-up is
cancelled when the accelerator
pedal is pressed, and resumed
when the pedal is released.
Warm-up is automatically cancelled
entirely after the engine coolant
temperature rises above 65 °C
(149 °F).Winter Cover
.Do not cover the front of the
radiator with newspapers,
cardboard or any other
flammable material to raise the
engine coolant temperature.
. If you allow the engine to warm
up but the engine coolant
temperature does not rise, have
the nearest dealer inspect the
thermostat.
Radiator Grille Covers
{Warning
Radiator shutters, winter fronts,
or grille covers are not to be used
and may cause the engine's
radiator cooling fan to fatigue
from the alternate unloading and
loading of the blades as they
pass by the masked area
followed by the unmasked area.
After the fan has been fatigued, it
may suddenly break apart while
rotating, possibly causing (Continued)
Warning (Continued)
personal injury to anyone
standing nearby, and equipment
damage. You and others could be
seriously injured.
Engine Heater
Engine Block and Oil Pan Heater
If the vehicle is parked in a garage,
the block and pan heaters should
not be needed until the garage
temperature drops below −23°C
(−10°F) regardless of outside
temperature.
The engine block and oil pan
heaters are designed to warm the
block and oil pan areas that will let
the engine run faster. To use the
heaters:
1. On single cab vehicles, tilt the cab. See Cab Tilting 0233.
2. Unwrap the electrical cord and remove the protective cap.

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
164 Driving and Operating
3. Plug the cord into anythree-prong 110 volt outlet
(normal household current).
It may require several hours to
sufficiently heat the engine.
Outside temperature, oil
viscosity, etc., will affect how
long the block and oil pan
heater should remain plugged
in. Contact your dealer for the
conditions in your area.
4. After using the heater(s), be sure to restore the cord
properly, to help keep it away
from moving engine parts.
If the cord is too short, use a heavy
duty, three-prong extension cord. Do
not use an extension cord such as
you would use for a lamp, because
the cord may overheat.
The engine should go through a
warm-up period to warm up the
engine oil before placing engine
under load. This will ensure proper
lubrication of the engine.Engine Alarm and
Automatic Shutdown
If the system senses any of the
following conditions: high engine
temperature, low engine oil pressure
or low engine coolant, the
corresponding warning light and
engine alarm (shutdown) warning
light will come on. If the engine
alarm (shutdown) warning light
comes on, you will also hear a tone
alarm.
If your vehicle has the engine
shutdown feature, your engine will
shut down in 30 seconds. Pull safely off the road and shut off
the engine. Do not start it until the
cause of the problem is known, and
the problem is fixed. However, if the
engine shuts down when you are
still in traffic, you can restart the
engine and get another 30 seconds
of operation. Do this only if you
have to, since there is a problem
that can harm the engine if it is not
fixed. See
Engine Shutdown
Warning Light 068.
Idle Shutdown
Idle Stop is a dealer programmable
function which will automatically turn
off the engine, at idle, when specific
programmed conditions are met.
See your dealer for details. When
the Idle Stop light comes on, it alerts
you that programmed conditions
have been met and the engine is
about to shut down. This light stays
on after the engine has stopped.
This indicator light will come on
when the engine control switch is
turned to the ON position and then
should go out after approximately
3 seconds.

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
184 Driving and Operating
5. Turn the engine control switchto the LOCK position.
The DEF freezes at approximately
−11 °C (12 °F).
In cold weather, when the vehicle is
left without performing these actions
and the DEF tank freezes, the low
DEF level warnings and indicators
may not turn off when DEF is added
until after the tank defrosts.
Make sure to stop the engine before
adding the DEF. See Warning
Buzzers 079.
When DEF Freezes
Engine coolant circulates through
the DEF tank to thaw it when frozen
and prevent it from freezing while
the engine is running. The vehicle
can be driven normally when DEF is
frozen in the DEF tank.
If the Refill DEF warning light is on
and the remaining DEF in the DEF
tank is frozen, the vehicle low level
warning system cannot be reset by
adding DEF. The DEF gauge will not
register correctly should the
remaining DEF freeze at this level. Move the vehicle to a location to
allow the DEF to thaw. Once the
DEF is thawed the DEF gauge
should read correctly allowing the
low level warning system to reset.
To avoid this condition follow the
instructions for Adding DEF in Cold
Weather.
{Warning
Do not warm up the DEF tank
using a burner, heater, etc. You
and others could be seriously
injured.
DEF Storage
Seal the container and store it in an
indoor place with good ventilation
avoiding direct sunlight.
When storing DEF, the shelf life
varies depending on the room
temperature of the storage place.
For details, please contact the
distributor of the DEF. For storage of DEF, seal the
container to prevent the moisture
from evaporating.
Even when DEF has been frozen,
its quality is maintained when it is
thawed. It can be used as it is.
To store or carry DEF, use the
original container in which the DEF
was kept at the time of purchase.
Also, if other containers are used,
prepare a clean container for
exclusive use, which can be a
polyethylene resin tank (PE) or
stainless steel container, and do not
introduce foreign matter such as
water or contamination.
DEF Disposal
Do not dispose of DEF and the
empty container into lakes, marine
areas, rivers, etc. DEF must be
disposed of in a method conforming
to the regulatory requirements in
your state.

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
246 Vehicle Care
{Warning
For storage, close the cap of
coolant container securely and
keep it in a place inaccessible to
children.
You and others could be seriously
injured.
Using any coolant other than that
recommended by your dealer could
cause damage to the engine,
radiator or heater core. In particular,
use of coolants containing borate
salts or silicates may result in
engine or radiator corrosion,
causing engine coolant leaks and
other problems.
To dilute the coolant, use distilled
water or deionized water.
Do not use the coolant at any
coolant concentration other than
that specified. If the coolant
concentration is 60% or higher,
overheating is likely to occur, while
if it is 30% or lower, anti-corrosion
function is not provided sufficiently. Using coolant at any coolant
concentration other than that
specified may reduce anti-freezing
performance, and engine coolant
may freeze.
If the engine coolant decreases
rapidly, stop the vehicle in a safe
place and contact your dealer for
advice and repair.
Checking the Engine Coolant
Level
For the single cab model, the
engine coolant reserve tank is
located behind the front-right wheel.
See
Cab Tilting 0233.
For the crew cab model, the engine
coolant reserve tank is under the
access panel beneath the left rear
seat. See Engine Cover 0235.
When the engine has cooled down,
make sure that the fluid level in the
engine coolant reserve tank is no
lower than the “MIN”line. In
addition, carefully remove the
radiator cap and check to see if it is
damaged. Check that the engine
coolant is full to the filler neck.
Check the engine coolant level only
when it is cold.

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
250 Vehicle Care
If Steam Is Not Coming from the
Engine CompartmentIf the engine coolant temperature
gauge shows an overheat condition,
or you have reason to suspect the
engine may be overheating, take
the following steps:1. Operate the hazard warning flasher and pull the vehicle
immediately over to a safe
place that does not impede
traffic and park it.
2. Idle the engine and wait until the engine coolant temperature
drops to safety zone. If your air
conditioner (if equipped) is on,
turn it off. And turn on the
heater to help the engine
expel heat.
3. When the needle of the engine coolant temperature gauge
returns to the middle of the
safety zone, stop the engine.
If the needle of engine coolant
temperature gauge does not
drop inside into the safety
zone, turn the engine off and
have your vehicle serviced at
the nearest dealer. When the cooling fan for the
radiator is not turning, turn off
the engine immediately.
{Warning
Even when the engine has been
stopped, the engine coolant in the
radiator remains under pressure.
Immediately removing the radiator
cap could cause steam or hot
water to blow out, and you could
be scalded as a result. The
engine coolant in the reserve tank
may also be hot. Immediately
removing the cap could cause hot
water to blow out, and possibly
scald you. Perform inspection,
refilling, and replacement of
coolant only when its temperature
has cooled.
When removing the radiator cap
and reserve tank cap, use a thick
cloth to cover the cap and turn it
little by little.
You and others could be seriously
injured.

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
Vehicle Care 251
4. If no steam or engine coolantcan be seen or heard from the
engine compartment:
.Tilt the cab or open the
engine access cover.
‐If the engine coolant is
boiling, wait until it stops
before proceeding.
‐ Look at the see-through
reserve tank. The
engine coolant level
should be between the
"MAX" and "MIN" lines
on the reserve tank.
‐ If necessary, pour
engine coolant (See
Engine Coolant 0243
for the proper coolant
and water mixture) into
the reserve tank only,
not directly into the
radiator. Also, do not
check engine coolant
level at the radiator.
. Make sure the fan belts are
not broken, or off the
pulleys, and that the fan
turns when the engine is started. Make sure the fan
blade and pulleys are not
broken.
. Check the radiator hoses
and connections, heater
hoses and connections,
radiator, water pump, EGR
cooler, and SCR system
and hoses for leakage.
If you do not find a leak or
other problem, carefully add
engine coolant to the
reserve tank.
If the engine coolant level in
the reserve tank is at the
correct level but there is still
an indication on the
instrument panel of an
overheat condition:
You must let the engine
cool first. You may then add
engine coolant directly to
the radiator. See “Adding
Engine Coolant” under
Engine Coolant 0243.
5. Inspect to see if there is any dirt, etc. attached to the front
surface of the radiator. Also, inspect to see if there is
anything blocking the core.
If there is anything attached,
clean and remove it.
6. After the inspection, regardless of the vehicle condition, please
contact the nearest dealer.
Once the engine coolant
temperature gauge no longer
signals an overheat condition, you
can resume driving at a reduced
speed. Return to normal driving
after about 10 minutes if the gauge
pointer does not again show an
overheat condition.
When tap water only has been used
for engine coolant in an emergency,
change the engine coolant as soon
as possible.
Engine damage may be caused if
an overheating engine is suddenly
refilled with water. Instead, refill
slowly.

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
280 Vehicle Care
Fuse and Relay Location–Cab InteriorFuse locations:
No. Description Rating
1 RR P / WINDOW 25A
2 – –
3 ROOM LAMP, AUDIO 10A
4 DOOR LOCK 15A
5 TRAILER BRAKE 15A
6 P/ WINDOW 25A
7 ABS 10A
8 WIPER 25A
9 H / LAMP LO (LH) 10A
10 LAMPS (BATT) 10A 11 H / LAMP LO (RH) 10A
12 BRAKE LAMPS 10A
13 STARTER 10A
14 H / LAMP HI (LH) 10A
15 H / LAMP HI (RH) 10A
16 MIRROR HEATER 15A