2020 CHEVROLET LOW CAB FORWARD overheating

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 249
Engine Overheating
When the Engine Overheats
The engine cooling system may
overheat if the engine coolant level
is too low, if there is a sudden loss
of engine coolant (such as radiator
hose failure), or if other problems
occur. It may also temporarily
overheat during severe operating
conditions such as:
.Climbing a long hill on a hot day.
. Stopping after high-speed
driving.
. Idling for long periods in traffic.
If engine power drops and the
needle on the engine coolant
temperature gauge goes up above
the upper limit of the safety zone
and enters the "H" zone, the engine
is overheating. The engine overheat
warning light will come on and the
warning buzzer will sound. Either
steam or boiling engine coolant will
squirt out of the radiator. The
vehicle will also have an “OVERHEAT”
message displayed. Take the
following corrective actions
immediately.{Warning
To help avoid being burned:
Do not tilt the cab or open the
engine access cover if you see or
hear steam or engine coolant
escaping from the engine
compartment. Wait until no steam
or engine coolant can be seen or
heard before tilting the cab or
opening the engine cover.
Do not remove the radiator cap or
engine coolant reserve tank cap if
the engine coolant in the tank is
boiling. Also do not remove the
radiator cap while the engine and
radiator are still hot. Scalding fluid
and steam can be blown out
under pressure if either cap is
taken off too soon.
You and others could be seriously
injured. If Steam Is Coming from the
Engine Compartment
{Warning
If the engine coolant temperature
gauge shows an overheat
condition or you have other
reasons to suspect the engine
may be overheating, continued
operation of the engine (other
than as described here) even for
a short period of time may cause
a fire and the result in personal
injury and severe vehicle
damage. Take immediate action
as outlined.
You and others could be seriously
injured.
If you see or hear escaping steam
or have any other reason to suspect
there is a serious overheat
condition, stop and park the vehicle
as soon as it is safe to do so, turn
on the hazard warning flasher and
then turn off the engine immediately
and safely exit the vehicle.

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
Technical Data 355
Engine Drive Belt Routing
Fan Belt and Air Conditioning
Compressor Belt
See theMaintenance Schedule
0 317.
No. Name
1 Fan belt
2 Fan pulley
3 A/C belt
4 A/C compressor
5 Tension pulley
6 Crank pulley No.
Name
7 Alternator
If your air conditioning system is
functioning properly, it is not
necessary to remove and replace
the refrigerant or compressor oil.
. A V-ribbed belt is used for the
fan belt. This type of belt
requires the tension to be
adjusted more accurately than is
required with the conventional V
belt. Inappropriate tension could
cause the belt to make noise or
break. When the fan belt is
damaged, electricity is not
properly generated or becomes
a cause of engine overheating.
You must check the tension of
the fan belt carefully.
. Use dealer-certified genuine
parts when changing the
fan belt.
. Have the vehicle inspected and
serviced at your dealer. .
The air conditioning drive belt,
if equipped, must be adjusted
after fan belt adjustment. If the
belt is not adjusted properly, the
A/C belt may experience
excessive tension, and possible
premature failure.

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
Index 367
D
Damage Repair, Collision . . . . . . . 359
Danger, Warning, and Caution . . . . 3
Daytime Running Lamps (DRL)Indicator Light . . . . . . . . . . . . . . . . . . 69
Devices Auxiliary . . . . . . . . . . . . . . . . . . . . . . 107
Diesel Engine Engine Alarm andAutomatic Shutdown . . . . . . . . 164
Diesel Exhaust Fluid . . . . . . . . . . . . 180
Diesel Exhaust Fluid (DEF) Gauge . . . . . . . . . . . . . . . . . . . . . . . . . 60
Diesel Exhaust Fluid (DEF)
Warning Light . . . . . . . . . . . . . . . . . . 68
Diesel Particulate Filter . . . . . . . . . 171
Distracted Driving . . . . . . . . . . . . . . . 130
Dome Lamps . . . . . . . . . . . . . . . . . . . . 84
Door Locks . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Power Locks . . . . . . . . . . . . . . . . . . . . 21
Drive Belt Routing, Engine . . . . . . 355
Driver Behavior . . . . . . . . . . . . . . . . . 129
Driver Information Center (DIC) . . . . . . . . . . . . . . . . . . . 70
Driving Better Fuel Economy . . . . . . . . . 129
Emergencies . . . . . . . . . . . . 145, 155 Driving (cont'd)
Hill and Mountain Roads . . . . . . 141
If the Vehicle is Stuck . . . . . . . . . 144
Wet Roads . . . . . . . . . . . . . . . . . . . 140
Winter . . . . . . . . . . . . . . . . . . . . . . . . 142
E
Electrical Equipment,
Add-On . . . . . . . . . . . . . . . . . . . . . . . 227
Electrical System
Overload . . . . . . . . . . . . . . . . . . . . . 277
Emergencies . . . . . . . . . . . . . . 145, 155
Engine Air Cleaner/Filter . . . . . . . . . . . . . 243
Alarm and Automatic
Shutdown . . . . . . . . . . . . . . . . . . . 164
Check Light (Malfunction Indicator) . . . . . . . . . . . . . . . . . . . . . . 61
Checks Before Operating . . . . . 166
Compartment Overview . . . . . . . 234
Coolant . . . . . . . . . . . . . . . . . . . . . . . 243
Coolant Temperature Gauge . . . . 60
Cover . . . . . . . . . . . . . . . . . . . . . . . . . 235
Drive Belt Routing . . . . . . . . . . . . 355
Exhaust . . . . . . . . . . . . . . . . . . . . . . 168
Heater . . . . . . . . . . . . . . . . . . . . . . . . 163
High Idle System . . . . . . . . . . . . . 165
Oil Pressure Light . . . . . . . . . . . . . . 67 Engine (cont'd)
Overheating . . . . . . . . . . . . . . . . . . 249
Reduced Power Light . . . . . . . . . . . 69
Running While Parked . . . . . . . . 170
Shutdown Warning Light . . . . . . . . 68
Engine Oil Level Indicator Light . . . . . . . . . . . . 67
Engines Diesel Fuel . . . . . . . . . . . . . . . . . . . 218
Exhaust Brake . . . . . . . . . . . . . . . . . . 213
Exhaust Brake Light . . . . . . . . . . . . . 65
Exhaust Fluid Diesel . . . . . . . . . . . . . . . . . . . . . . . . 180
Extender, Seat Belt . . . . . . . . . . . . . . 37
Exterior Lamp Controls . . . . . . . . . . 80
F
Filter . . . . . . . . . . . . . . . . . . . . . . . . . . . . 171 Fuel . . . . . . . . . . . . . . . . . . . . . . . . . . 260
Filter, Engine Air Cleaner . . . . . . . . . . . 243
Fixed Mast Antenna . . . . . . . . . . . . . 90
Flash-to-Pass . . . . . . . . . . . . . . . . . . . . 81
Flashers, Hazard Warning . . . . . . . 82
Flat Tire . . . . . . . . . . . . . . . . . . . . . . . . 300
Fluid Automatic Transmission . . . . . . 241
Brakes . . . . . . . . . . . . . . . . . . . . . . . . 258

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
Index 369
L
LampsCargo . . . . . . . . . . . . . . . . . . . . . . . . . . . 84
Cornering . . . . . . . . . . . . . . . . . . . . . . . 83
Dome . . . . . . . . . . . . . . . . . . . . . . . . . . . 84
Exterior Controls . . . . . . . . . . . . . . . . 80
Interior . . . . . . . . . . . . . . . . . . . . . . . . 277
License Plate . . . . . . . . . . . . . . . . . 276
Malfunction Indicator (CheckEngine) . . . . . . . . . . . . . . . . . . . . . . . 61
Roofmarker . . . . . . . . . . . . . . . . . . . 274
Sidemarker . . . . . . . . . . . . . . . . . . . 274
Lap Belt . . . . . . . . . . . . . . . . . . . . . . . . . 36
Lighting Illumination Control . . . . . . . . . . . . . 83
Lights Antilock Brake System(ABS) Warning . . . . . . . . . . . . . . . . 64
Automatic Transmission
Fluid Temperature . . . . . . . . . . . . . 66
Battery Warning . . . . . . . . . . . . . . . . 61
Brake System Warning . . . . . . . . . 62
Check Engine (Malfunction Indicator) . . . . . . . . . . . . . . . . . . . . . . 61
Cruise Control . . . . . . . . . . . . . . . . . . 70
Daytime Running Lamps (DRL) . . . . . . . . . . . . . . . . . . 69
Diesel Exhaust Fluid (DEF) . . . . . 68 Lights (cont'd)
Engine Oil Level Indicator . . . . . . 67
Engine Oil Pressure . . . . . . . . . . . . 67
Engine Shutdown Warning . . . . . 68
Exhaust Brake . . . . . . . . . . . . . . . . . . 65
Flash-to-Pass . . . . . . . . . . . . . . . . . . . 81
High-Beam On . . . . . . . . . . . . . . . . . . 69
High/Low Beam Changer . . . . . . . 81
Idle Shutdown . . . . . . . . . . . . . . . . . . 68
Overdrive Off . . . . . . . . . . . . . . . . . . . 66
Reduced Engine Power . . . . . . . . 69
Seat Belt Reminders . . . . . . . . . . . . 60
Service Transmission
Warning . . . . . . . . . . . . . . . . . . . . . . . 65
Service Vehicle Soon . . . . . . . . . . . 62
Wait to Start . . . . . . . . . . . . . . . . . . . . 67
Loading the Vehicle . . . . . . . . . . . . . . 46
Locks Door . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Power Door . . . . . . . . . . . . . . . . . . . . . 21
M
Maintenance and CareAdditional . . . . . . . . . . . . . . . . . . . . . 336
Maintenance Schedule . . . . . . . . . 317 Recommended Fluids andLubricants . . . . . . . . . . . . . . . . . . . 339
Malfunction Indicator Lamp . . . . . . 61 Messages
Vehicle . . . . . . . . . . . . . . . . . . . . . . . . . 74
Mirrors . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 Heated . . . . . . . . . . . . . . . . . . . . . . . . . 22
N
New Vehicle Break-In . . . . . . . . . . . 156
Noise Control System . . . . . . . . . . 262
O
Odometer . . . . . . . . . . . . . . . . . . . . . . . . 58Trip . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58
Oil
Engine . . . . . . . . . . . . . . . . . . . . . . . . 235
Pressure Light . . . . . . . . . . . . . . . . . . 67
Online Owner Center . . . . . . . . . . . 357
Operating Temperature . . . . . . . . . 162
Outlets Power . . . . . . . . . . . . . . . . . . . . . . . . . . 55
Overdrive Off . . . . . . . . . . . . . . . . . . . 206
Overdrive Off Light . . . . . . . . . . . . . . 66
Overheating, Engine . . . . . . . . . . . . 249
Overview Instrument Panel . . . . . . . . 8, 10, 11
Owner Checks and Services . . . . 330