check engine CHEVROLET LOW CAB FORWARD 2020 Owners 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
Driving and Operating 223
Fuel will be mixed in the drained
water. Dispose of it in a method
conforming to the regulatory
requirements in your state.
If the water separator (fuel filter)
requires frequent draining, have the
fuel system inspected at your
dealer.
Pre Fuel Filter (Chassis-side)1. Attach a plastic hose to the drain plug (2) on the bottom of
the chassis-side fuel filter and
put the other end of the hose in
a container placed beneath the
filter. 2. Loosen the drain plug and
move the priming pump (1) up
and down by hand between
10 and 20 times.
3. Fully tighten the drain plug (2) and move the priming pump (1)
several times.
Fuel Filter (Engine-side)1. Attach a plastic hose to the drain plug (2) on the bottom of
the engine-side fuel filter (1)
and put the other end of the
hose in a container placed
beneath the filter.
2. Loosen the drain plug andmove the priming pump up and
down by hand between 10 and
20 times.
3. Fully tighten the drain plug and move the priming pump several
times.
4. Test run the engine and check that there are no fuel leaks
from the drain plug of the
engine-side fuel filter. Also
check that the water separator
(fuel filter) warning light
stays off.

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.

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 227
Conversions and
Add-Ons
Add-On Electrical
Equipment
Installing Electrical Equipment
{Warning
Inappropriate installation or
removal of audio, radio or other
electrical equipment can
adversely affect other electrical
equipment and cause a
breakdown or fire. Be sure to
have electrical equipment
installed or removed by your
dealer. You and others could be
seriously injured.
Do not install any unauthorized
radio set, or any radio set or
antenna that does not comply with
relevant standards. Noise from the
radio set could cause
electromagnetic interference with
the vehicle's electronic equipment and other systems, resulting in a
vehicle breakdown or in a
malfunction of electronic equipment.
Consult your dealer if you wish to
install radio equipment.
Power Take-Off (PTO)
If equipped, the PTO is a device
that is used to provide engine power
to special equipment directly from
the engine or through the
transmission. For details about the
PTO operation, refer to the separate
instruction manual provided by its
maker.
If the optional PTO function is used
for long periods of time, make sure
to regularly check the diesel
particulate filter (DPF) indicator.
Automatic DPF regeneration will not
take place while the PTO function is
active.
1. Engine Speed Control
Switch
2. Main Switch
{Warning
In PTO mode, Cruise Set/Resume
Switch can be used exactly the
same as PTO Engine Speed
Control Switch. Improper
operation of these switches may
cause personal injury or damage.

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 229
Vehicle Care
General Information
General Information . . . . . . . . . . 230
California Proposition65 Warning . . . . . . . . . . . . . . . . . 230
California Perchlorate Materials Requirements . . . . . 230
Accessories and Modifications . . . . . . . . . . . . . . . . 230
Vehicle Checks
Doing Your OwnService Work . . . . . . . . . . . . . . . 231
Cab Tilting . . . . . . . . . . . . . . . . . . . . 233
Engine Compartment Overview . . . . . . . . . . . . . . . . . . . . 234
Engine Cover . . . . . . . . . . . . . . . . . 235
Engine Oil . . . . . . . . . . . . . . . . . . . . 235
Automatic Transmission Fluid . . . . . . . . . . . . . . . . . . . . . . . . 241
Engine Air Cleaner/Filter . . . . . . 243
Engine Coolant . . . . . . . . . . . . . . . 243
Engine Overheating . . . . . . . . . . 249
Power Steering Fluid . . . . . . . . . 252
Washer Fluid . . . . . . . . . . . . . . . . . 252
Brakes . . . . . . . . . . . . . . . . . . . . . . . 253
Brake Fluid . . . . . . . . . . . . . . . . . . . 258
Battery - North America . . . . . . 259 Fuel Filter . . . . . . . . . . . . . . . . . . . . 260
Rear Axle (Gear Oil Viscosity
Chart) . . . . . . . . . . . . . . . . . . . . . . . 261
Rear Axle (Oil Level Check) . . . . . . . . . . . . . . . . . . . . . . 262
Noise Control System . . . . . . . . 262
Automatic Transmission Shift Lock Control Function
Check . . . . . . . . . . . . . . . . . . . . . . . 264
Wiper Blade Replacement . . . . 265
Headlamp Aiming
Headlamp Aiming . . . . . . . . . . . . 267
Bulb Replacement
Bulb Replacement . . . . . . . . . . . . 267
Headlamps and Front Turn Signal . . . . . . . . . . . . . . . . . . . . . . . 270
Roofmarker Lamps . . . . . . . . . . . 274
Sidemarker Lamps (Including Turn Signal and Cornering
Lamps) . . . . . . . . . . . . . . . . . . . . . . 274
Taillamps, Turn Signal, Stoplamps, and Back-Up
Lamps . . . . . . . . . . . . . . . . . . . . . . 276
License Plate Lamp . . . . . . . . . . 276
Interior Lamps . . . . . . . . . . . . . . . . 277
Electrical System
Electrical System Overload . . . 277
Wheels and Tires
Wheels and Tires . . . . . . . . . . . . . 285
Tire Pressure . . . . . . . . . . . . . . . . . 297
Tire Rotation . . . . . . . . . . . . . . . . . 297
If a Tire Goes Flat . . . . . . . . . . . . 300
Jump Starting
Jump Starting - North America . . . . . . . . . . . . . . . . . . . . . 301
Towing the Vehicle
Towing the Vehicle . . . . . . . . . . . 305
Appearance Care
Exterior Care . . . . . . . . . . . . . . . . . 307
Interior Care . . . . . . . . . . . . . . . . . . 313

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 231
Vehicle Checks
Doing Your Own
Service Work
Precautions for Checking and
Adjustments
Your authorized dealer has trained
technicians and genuine parts to
service your vehicle properly. For
expert advice and quality service,
see your authorized dealer.
{Warning
To help avoid personal injury, take
care when doing any
maintenance or making any
check or repair. Follow
manufacturer's instructions for all
materials used during service and
maintenance of this vehicle.
If used or handled improperly,
they may be hazardous. Improper
or incomplete service can also
affect the vehicle and result in(Continued)
Warning (Continued)
personal injury, or damage to the
vehicle or its equipment. If you
have any questions about
carrying out some service, have
the work done by a skilled
technician.
To prevent personal injury, keep
hands, tools and clothing clear of
the engine cooling fan when the
engine is running.
The engine, exhaust pipe and
radiator will be hot immediately
after the vehicle is driven. Be
careful around these parts to
prevent burns. Perform all checks
when the engine is cold.
Do not perform work near an
open flame or other heat sources.
Do not let the engine run in poorly
ventilated garages or sheds. This
could cause carbon monoxide
poisoning.(Continued)
Warning (Continued)
Performing maintenance work on
a truck or chassis can be
dangerous. In trying to do some
jobs, you can be seriously injured.
Do your own maintenance work
only if you have the required
know-how and the proper tools
and equipment for the job. If you
have any doubts, contact your
dealer.
You and others could be seriously
injured.
Pull firmly on the parking brake
lever and move the selector lever to
"P" and make sure the shift indicator
displays "P".
Make sure to turn off the engine and
remove the key from the engine
control switch before performing any
checks.
Select a place with a solid and level
surface to perform the checking and
maintenance work. Make sure to

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
232 Vehicle Care
chock the wheels. It would be very
dangerous if the vehicle started
to move.
When performing work on the
electrical system, begin by turning
the engine control switch to the
"LOCK" position, wait at least
3 minutes, and then disconnect the
negative cable from the negative
terminal on battery. If the negative
cable is disconnected within
3 minutes, the engine control
module may malfunction.
When working on the fuel line or
fuel filter, remove the fuel tank filler
cap. The fuel system is under
pressure and the fuel will overspill
unless the pressure is relieved,
possibly leading to combustion or
a fire.
Do not make engine adjustments
yourself. Be sure to consult your
dealer.
Use only appropriate tools.
Oils, brake fluid and engine coolant
have lubrication, cooling and rust
prevention functions. If these liquids
deteriorate through loss orcontamination, it will cause a
decline in the performance of the
parts and such problems as seizure
or malfunctioning. Replenish or
change these liquids when
performing the checks (daily and
periodic checks) as required by the
relevant regulations or in
accordance with the Maintenance
Schedule (when either the specified
driving distance or period of time,
whichever comes first, has expired).
Confirm that all systems and
components are normal after
performing the work.
Do not leave the removed parts or
tools in the engine compartment.
They could damage the equipment if
caught in the belts or other moving
components.
Dirty water, dirt and other impurities
seriously impair the effectiveness of
the oil, grease and fluids, and
damage the parts. Exercise all due
caution to prevent waste or other
refuse from coming in contact with
parts or materials that have been
removed when changing or
replenishing them.Do not step on the engine or climb
onto it. You could cause an engine
failure by, for example, damaging
the cylinder head cover or various
connectors.
Electric Welding
Careless electric welding of vehicle
parts can cause welding current to
flow back through the vehicle’s
ground circuit and damage electrical
and electronic parts so that they do
not function normally. Whenever
electric welding is necessary,
consult your dealer.

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 233
Cab Tilting
Before Tilting the Cab (Single Cab
Model)
{Warning
To help avoid personal injury and
property damage:. Park the vehicle on level
ground and check that there
is enough space in front of
and above the cab.
. Set the parking brake firmly
and block the front wheels.
. Move the selector lever in
the "P" position.
. Secure loose articles in
the cab.
. Stop the engine.
. Close the cab door.
. Keep the area surrounding
the cab clear.
You and others could be seriously
injured. Tilting the Cab
1. Check that all personnel are clear of the cab.
2. Unlock the handle (2) whilepulling the lever (1).
3. Hold the assist handle (3) andpull the safety hook (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
Vehicle Care 235
Engine Cover
Engine Inspection Cover (Crew
Cab Model)
To gain access to the engine,
release the catch hooks (3) and
raise the passenger’s seat
cushion (2). The cover can be held
up by a strap (1), permitting engine
inspection and adjustment. Engine Inspection Sub Cover
(Crew Cab Model)
To gain access to the engine
compartment, pull the lock lever
(red) (1) on the driver
’s seat
cushion (2) to unlock it, raise the
driver ’s seat cushion and remove
the sub cover. Engine Coolant Reserve Tank
Inspection Cover (Crew Cab
Model)To gain access to the engine
coolant reserve tank, remove the
inspection cover located under the
rear left seat.
Engine Oil
Engine oil is an important factor
determining engine performance
and longevity. Be sure to use only
the specified oil and oil filters. The
engine oil level must be checked

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
236 Vehicle Care
and the oil should be changed
regularly according to the
Maintenance Schedule.
The engine oil performs the
following important functions:
.It prevents engine parts from
becoming worn.
. It cools engine parts.
. It cleans engine parts.
. It seals the combustion
chambers and prevents rust.
Replace the engine oil at regular
intervals.
When particulate matter (PM) has
accumulated to a preset level in the
diesel particulate filter (DPF), the
filter is automatically regenerated
through combustion. To make this
regeneration (combustion) possible,
a small amount of fuel is injected
into the engine combustion chamber
after firing. This causes fuel to
gradually become mixed with the
engine oil, and the engine oil level
may rise beyond the original level.
This does not indicate a malfunction
of the engine.Access to the Engine
Single Cab Model
Access to the engine oil dipstick is
located on the engine left side after
tilting the cab. See Cab Tilting
0 233.
Crew Cab Model
The engine oil dipstick is under the
engine inspection sub cover located
beneath the driver's seat.
Checking the Engine Oil Level
Press the engine oil level check
switch. If engine oil level is low the
red oil pressure warning light will
turn on. If the engine oil level is
above the "OK", the green oil level
indicator will turn on.
The oil level varies while the engine
is running, right after it is stopped,
and on sloping ground. When
checking the oil level, be sure the
vehicle is on level ground while the
engine is cool.

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 237
The engine oil level must be kept at
the right level to help assure proper
lubrication of your vehicle's engine.
It is the owner's responsibility to
check the oil level at regular
intervals (such as every fuel stop),
according to the following
instructions. Park the vehicle on a
level surface and check the engine
oil level before starting or at least
30 minutes after turning off the
engine.
1. Remove the oil dipstick (2) andwipe off any oil on the oil
dipstick.
2. Reinsert the oil dipstick fullyand then gently remove it.
The oil is at the correct level if
the oil level is between the
"FULL" and "MIN" marks.
3. If the oil level is too low, add oil to the "FULL" mark.
4. Reinstall the oil dipstick into position after checking the oil
level.
Any oil level above the "FULL" mark
on the oil dipstick may cause engine
malfunctions. The oil level cannot be checked
correctly when the engine is
running.
If the engine has been running, wait
at least 30 minutes before checking.
Adding the Engine Oil
When the engine oil level is near or
below the "MIN" mark on the oil
dipstick, remove the oil filler cap (1)
and add the oil. Remove the oil
dipstick (2) at this time. Use only the
specified engine oil.