coolant level CHEVROLET LOW CAB FORWARD 2020 Owner's 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
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
Vehicle Care 247
The radiator cap (1) opens and
closes in double action. When
removing the radiator cap, take
caution not to damage the cap and
the filler neck (2).
Turn the cap slowly to the left until it
reaches a“stop”. Do not press down
while turning the cap.
Wait until any remaining pressure
(indicated by a hissing sound) is
relieved, then press down on the
cap and continue turning it to
the left.
Also, check to make sure there are
no leaks from the radiator or
radiator hose. Check for fluid or stains on the ground showing leaks
where the vehicle is parked. Contact
your dealer if you discover leaks.
Using the vehicle when there are
leaks can lead to engine seizure.
Adding Engine Coolant
Single Cab Model
Crew Cab Model
When the engine coolant level in the
engine coolant reserve tank is
below the “MIN”line, open the
reserve tank cap and fill to near the
“MAX” line with engine coolant.
Wash the reserve tank cap and filler
neck with clean water. Tighten the
cap securely after the engine
coolant has been replenished.

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
248 Vehicle Care
1. When the engine is cool,remove the radiator cap (1).
.Turn the cap slowly to the
left until it reaches a “stop”.
Do not press down while
turning the cap.
. Wait until any remaining
pressure (indicated by a
hissing sound) is relieved,
then press down on the cap
and continue turning it to
the left.
2. Fill the radiator to the base of the filler neck (2) and install the
radiator cap. Add enough engine coolant to provide for
required cooling, freezing, and
corrosion protection.
3. Run the engine until the engine coolant temperature rises to
normal level, and idle the
engine for 10 minutes.
4. Install the radiator cap.
Check, replenish or change the
engine coolant only after the engine
has sufficiently cooled down.
When the engine is still hot, take
care to prevent engine coolant from
contact with the exhaust manifold.
Any such contact could result in
exhaust manifold damage.
If you use the proper quality engine
coolant, there is no need to add
extra inhibitors or additives which
claim to improve the system. They
may be harmful to the proper
operation of the system.
Do not overfill the engine coolant
reserve tank.
If the level of engine coolant
changes rapidly, have your vehicle
inspected at your dealer. Thermostat
The engine coolant temperature is
controlled by thermostat(s). The
thermostats stop engine coolant
flow through the radiator until a
preset temperature is reached. The
thermostats are installed in the
engine coolant outlet on the engine
block. The same thermostats are
used in both winter and summer.
When a replacement is needed,
genuine GM parts are
recommended.
Radiator Pressure Cap
The radiator cap, a 108 kPa (16 psi)
pressure type, must be installed
tightly, otherwise engine coolant
may be lost and damage to the
engine may result from overheating.
The radiator pressure cap should be
checked periodically for proper
operation. If a replacement is
required, a genuine GM part is
recommended.

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
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
Vehicle Care 253
properly wiped. At this time, also
check the spraying condition of the
windshield washer.
Inspect the washer fluid level
regularly, especially during bad
weather conditions.
Use a high quality premixed solvent
available at most dealers or service
stations.
Avoid hard water when mixing
windshield washer solvents. Hard
water contaminants may plug
orifices in the washer system and
reduce performance.
Do not use radiator antifreeze in the
windshield washer; it could cause
cab paint damage.
In cold weather, warm the
windshield with the defrosters
before using the washer, to help
prevent icing that may block the
driver's vision.Refilling Windshield Washer
Fluid
1. The windshield washer fluidtank (1) is located under the
instrument panel on the
passenger side.
2. Open the cap (2) and fill the tank with windshield washer
fluid.
Upon factory shipment, new
vehicles contain only tap water in
the washer fluid tank. Adjust the
concentration of the fluid to suit your
own usage. Follow the instructions provided with
the windshield washer fluid
regarding the ratio for mixing with
tap water.
Poor quality products, engine
coolant, and soapy water must not
be used. Failure to observe this
precaution can result in nozzle
blockage or damage to painted
surfaces.
The washer should never be used
while the tank is empty. Operating
the washer with the tank empty can
result in motor damage.Brakes
For the most effective braking and
for maximum life from brake system
components, follow these
suggestions:
.
Keep any obstructions from
interfering with brake pedal
travel.
. Keep tires properly inflated.
Improperly inflated tires can
reduce the efficiency of the
brakes.

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
326 Service and Maintenance
3. Engine Oil and Oil Filter :
Change at interval noted below
depending upon driving conditions.
•Normal Service —Change every
16 000 km (10,000 miles) or
12 months whichever occurs first.
• Severe Service —Change every
8 000 km (5,000 miles) or 3 months
if you often drive under one or more
of these conditions: (a) driving in
dusty areas, (b) frequent idling or
idling for long periods, (c) driving
6 km (4 miles) or less in freezing
weather, or other short trips in cold
weather, where the engine does not
thoroughly warm up.
Change oil and filter as soon as you
can after driving in a dust storm.
When recommended oil is used, it
conforms to this maintenance
schedule. (Recommended oil: CK-4
(API designations))
4. Fuel Filter : Replace the fuel
filter every 24 000 km (15,000 miles)
or more frequently if clogged or
replace when the fuel filter indicator
light comes on (if equipped). 5. Pre-Fuel Filter/Water
separator :
Replace the fuel filter
every 24 000 km (15,000 miles) or
more frequently if clogged or
replace when the fuel filter indicator
light comes on (if equipped).
6. Air Cleaner Filter : The level of
dirt in the air cleaner element can
be checked against the indicator.
Replace the air cleaner filter when
the Driver Information Center (DIC)
shows "CHECK AIR FILTER".
7. Damage to Air Intake Ducts and
Hoses : Check for damage of air
intake ducts and hoses and that
those are correctly installed every
24 000 km (15,000 miles) or
12 months. Replace or adjust those
if necessary.
8. Drive Belts : Check belt driving
the fan, alternator or A/C
compressor every 16 000 km
(10,000 miles). Look for cracks,
fraying, wear, and proper tension.
9. Engine Bolt Torques : Loosened
bolts result in lower engine output.
Check and adjust manifold mounting, and injectors to correct
torque every 80 000 km
(50,000 miles).
10. Rotate Tires :
To equalize wear,
rotate tires and adjust tire pressures
every 10 400 km (6,500 miles). See
Tire Rotation 0297.
11. Engine Cooling System : At
12 months or 16 000 km
(10,000 miles) intervals, wash
radiator cap and filler neck with
clean water, pressure test system
and radiator cap for proper pressure
holding capacity, tighten hose
clamps and inspect condition of all
cooling and heater hoses. Replace
hoses if cracked, swollen or
otherwise deteriorated. Have the
hoses replaced by your authorized
dealer.
12. Engine Coolant : Inspect the
engine coolant every 12 months.
Replace the engine coolant every
24 months, drain the engine coolant
by opening the drain plug at the
bottom of the radiator core, flush
and refill the engine cooling system
with a new engine coolant. Refer to
"Preparing Engine Coolant" in

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
Service and Maintenance 331
Recommended Daily
(Pre-operation) Inspections
These checks are in addition to, not
instead of, any legally required daily
inspections. See related topics
under "Maintenance Schedule",
especially if problems are found.
For safe and comfortable driving,
keep record of the distances driven
and the condition of the vehicle
during operation. Perform
inspections at appropriate intervals,
and perform maintenance in
accordance with the findings of the
inspections. If an inspection reveals
an abnormality or there was an
abnormality the previous time the
vehicle was driven, have the vehicle
repaired by the nearest dealer
before it is driven again.1. Components that showed abnormalities during the
previous operation
.Check components that
showed abnormalities
during the previous
operation 2. Checks performed at the
engine
.Fan belt looseness and
damage
. Engine oil level
. Engine coolant level
. Power steering fluid level
3. Checks performed from the driver's seat
.Brake fluid level
. Brake pedal free play
. Operation of meters,
gauges and warning/
indicator lights
. Engine startability,
abnormal noise and color of
exhaust gases
. Parking brake lever stroke
. Windshield washer fluid
spray condition and
windshield wiper
effectiveness
. Windshield washer fluid
level .
Steering wheel position and
free play
. Operation of horn and turn
signal lights
. Door lock operation
4. Checks performed during a walk around the vehicle
.Illumination, flashing,
contamination, damage and
obstruction of lights
. Contamination, damage ad
obstruction of windows,
mirrors and reflectors
. Leaf spring damage
. Oil, engine coolant, fuel,
brake fluid and power
steering fluid leaks
. Water separator
5. Checking wheels and tires .Air pressure
. Cracks and other damage
. Abnormal wear
. Tread depth

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
354 Technical Data
Parking Brake
Lever effective stroke (Under pull force of approx. 147 N (15 kg/33 lb) 6–8 notches
Electrical System
Battery type [BCI size] (RC-CCA) x No. of units 31T (160–950) x 2
*7
Starter
12 V/3.0 kw
Alternator 12 V/140 amp
Tightening Torque
Oil pan drain plug 83.3Y(8.5 kgf m/61.0 lb ft)
Oil filter drain plug —
Oil filter —
Oil filter cartridge 63.7Y(6.5 kgf m/47.0 lb ft)
Remarks:
*1see Engine Oil 0235.
Remarks:*2see Engine Coolant 0243.
Remarks:*3see Automatic Transmission Fluid 0241.
Remarks:*4see Rear Axle (Gear Oil Viscosity Chart) 0261 or
Rear Axle (Oil Level Check) 0262.
Remarks:
*5only for vehicles equipped with optional limited slip differential.
Remarks:*6The fuel tank capacity is stated on a metal plate attached to the fuel tank body. Only fill the tank to
95 percent of its capacity; this allows room for the expansion of the fuel.
Remarks:
*7larger capacity batteries 31 (180-930) × 2 can also be used. However, do not mix batteries of different
types and from different makers.

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