maintenance schedule 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
318 Service and Maintenance
training of dealer technicians
throughout the country and is
supported with a continuous
follow-up of publications and other
service information. The use of
genuine parts and accessories,
which have the same high quality
standards as original equipment
parts, and the use of factory
approved tools developed and
tested for use by the authorized
dealer also contribute to the high
quality of service.
If you have any questions on how to
keep your truck or chassis in good
condition, see your authorized
dealer, the place many truck owners
choose to have their maintenance
work done. Your authorized dealer
can be relied upon to use proper
parts and practices.
Some of these services can be
complex, so unless you are
technically qualified and have the
necessary equipment, you should
let your authorized dealer's service
department or another qualified
service center do these jobs.The schedule includes general
maintenance which you or a
qualified technician should perform
periodically.
Explanation of Vehicle
Maintenance and Log
The following is a brief explanation
of normal vehicle use.
NORMAL VEHICLE USE—The
maintenance instructions contained
in this section are based on the
assumption that your vehicle will be
used as designed:
.
To carry passengers and cargo
with the limitations indicated on
the vehicle VIN and GVW plate.
. On reasonable road surfaces
within legal operating limits.
. On a daily basis, as a general
rule, for at least several miles/
kilometers.
Unusual operating conditions, such
as driving in dusty areas (sweeper,
agricultural or off-road vehicles),
extended idling (refrigeration vehicles), or vehicles operated for
frequent short trips, will require
more frequent vehicle maintenance.
The log groups items according to
mile/kilometer service intervals. Use
the item codes (letter and number)
to find the description of the
maintenance and the time intervals.
Follow whichever interval comes
first, time or miles/kilometers.
After the maintenance services are
performed, insert the month, day
and mileage/ kilometers in the area
provided next to the serviced item.
The services shown up to
176 000 km (110,000 miles) are to
be repeated after the initial
176 000 km (110,000 miles) at the
same intervals.
Severe Driving Conditions
A vehicle operated under severe
conditions (see list below) requires
more frequent maintenance.
.
Frequent short trips of less than
6 kilometers (4 miles) in
moderate temperatures

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 319
.Frequent short trips of less than
16 kilometers (10 miles) in sub-
freezing temperatures
. Frequent and extended low-
speed engine operation (door-
to- door deliveries, stop- and- go
traffic, etc.)
. Driving on unpaved roads with
heavy dust
. Towing a trailer
Power Take Off (PTO) and
Extended Idle Use
When the vehicle is used with the
PTO equipment or used in a way
that requires extended idle time,
one hour of use shall be deemed
the same as 33 miles. See Driver
Information Center (DIC) 070 for
hourmeter.
Preventive Maintenance
As any mechanical device operates,
a certain amount of wear occurs.
The amount of wear depends on
certain variables –type and method
of operation and the schedule of
maintenance. These variables may be emphasized as critical to
malfunction but each is dependent
upon the other. For example, if a
vehicle is repeatedly overloaded,
driven at excessive speed or
improperly shifted, no schedule of
maintenance can prevent
malfunction. Also, if a preventive
maintenance schedule is not
followed, or is improperly carried
out, no amount of correct vehicle
operation will prevent malfunction.
If vehicle application, operation and
preventive maintenance schedules
and procedures are followed and
properly carried out, the life of the
vehicle will be greatly extended.
For example, regular attention to the
engine oil is essential. The oil level
must be periodically checked and oil
added whenever needed. Also, the
oil should be changed at the
intervals specified with the proper
quality and viscosity of oil. If your
engine should run excessively low
on oil or if the oil has lost its
lubricating qualities because of old
age, serious engine damage could
occur.
Maintenance Schedule Table
Letters Used to Indicate
Maintenance Service Types
I :
Inspect then clean, repair or
replace as necessary
A : Adjust
R : Replace
T : Tighten to the specified torque
L : Lubricate
C : Clean

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 325
maintenance intervals and may
cause a problem with engine
durability.
(3)Refer to "Air Cleaner Indicator
Light" under Engine Air Cleaner/
Filter 0243.
(4) Initial check at 1 040 km
(650 miles) is required.
(5) Be sure to discard used grease
seal, and always use new grease
seal for installation.
Explanation of Complete
Vehicle Maintenance Schedule
The following is a brief explanation
of each of the services listed in the
preceding Complete Vehicle
Maintenance Schedule.
1. Engine Noise : These
components have an effect on the
control of noise emissions. Service Interval Maintenance procedure
Engine
Every 16 000 km (10,000 miles) Inspect sound absorption materials for
tears, broken out sections or
attachment. Repair or replace as
necessary.
Cooling System
Every 16 000 km (10,000 miles) Inspect fan, shroud and radiator for
attachment, tears or cleanliness.
Replace as necessary.
Air intake system
Every 24 000 km (1,500 miles) Inspect all ducts, hoses and intake
silencers for leaks or chafing. Repair or
replace as necessary.
Exhaust system
Every 16 000 km (10,000 miles) Inspect silencer, pipes, gaskets, clamps
and mounting for exhaust gas leaks or
looseness. Repair or replace as
necessary.
Cab
Every 16 000 km (10,000 miles) Inspect sound absorption materials for
tears, broken out sections or
attachment. Repair or replace as
necessary.
2. Valve Lash : Incorrect valve
clearance will result in increased
engine noise and lower engine
output, thereby adversely affecting
engine performance. Retorque rocker shaft bracket nuts before
checking and adjusting valve
clearance.
Check and adjust valve clearance
every 80 000 km (50,000 miles) or
12 months whichever occurs first.

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
Service and Maintenance 333
Front
1. Roofmarker Lamp(Identification/
Clearance Lamp)
2. Front Turn Signal Lamp
3. Side Turn Signal Lamp/ Sidemarker Lamp
4. Cornering Lamp
5. Side Reflector
6. Headlamp/Parking Lamp
Rear
1. Rear Turn Signal Lamp
2. Back-up Lamp
3. License Plate Lamp
4. Taillamp/Stoplamp
Lubrication
One of the most important items of
good vehicle care is the lubrication
of all necessary points with the
Right Lubricant, at the Right Time
and in the Right Way. It is the
owner's responsibility to maintain
proper lubrication practices as
recommended in the following
pages. Greasing Chassis Components
The type (characteristics) of the
grease specified for use with a
chassis component differs from that
of the grease specified for use with
another component. Be sure to use
only the specified grease for each
component and perform greasing
according to the Maintenance
Schedule.
King pins (left and right)

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
358 Customer Information
G:View maintenance schedules,
alerts, and Vehicle Diagnostic
Information. Schedule service
appointments.
I: View and print dealer-recorded
service records and self-recorded
service records.
D: Select a preferred dealer and
view locations, maps, phone
numbers, and hours.
r: Track your vehicle’s warranty
information.
J: View active recalls by Vehicle
Identification Number (VIN). See
Vehicle Identification Number (VIN)
0 343.
H:Compare and shop for
Chevrolet and OnStar plans and
Services. View GM Card and
SiriusXM information (if equipped).
F: Chat with online help
representatives.
See my.chevrolet.com to register
your vehicle.
Chevrolet Owner Centre
(Canada) mychevrolet.ca
Visit the Chevrolet Owner Centre at
mychevrolet.ca (English) or
my.chevrolet.ca (French) to access
similar benefits to the U.S. site.
GM Mobility
Reimbursement Program
This program is available to
qualified applicants for cost
reimbursement of eligible
aftermarket adaptive equipment
required for the vehicle, such as
hand controls or a wheelchair/
scooter lift for the vehicle.
For more information on the limited
offer, visit www.gmmobility.com or
call the GM Mobility Assistance Center at 1-800-323-9935. Text
Telephone (TTY) users, call
1-800-833-9935.
Roadside Assistance
Program
Call 1-888-899-1327. (Text
Telephone (TTY): 1-888-889-2438.)
Service is available 24 hours a day,
365 days a year.
Calling for Assistance
When calling Roadside Assistance,
have the following information
ready:
.
Your name, home address, and
home telephone number.
. Telephone number of your
location.
. Location of the vehicle.
. Model, year, color, and license
plate number of the vehicle.
. Odometer reading, Vehicle
Identification Number (VIN), and
delivery date of the vehicle.
. Description of the problem.

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
362 Customer Information
Publication Ordering
Information
Service Manuals
Service manuals have the diagnosis
and repair information on the
engine, transmission, axle,
suspension, brakes, electrical
system, steering system, body, etc.
Customer Literature
Owner’s manuals are written
specifically for owners and are
intended to provide basic
operational information about the
vehicle. The owner ’s manual
includes the Maintenance Schedule
for all models.
Customer literature publications
available for purchase include
owner ’s manuals, warranty
manuals, infotainment manuals, and
portfolios. Portfolios include an
owner ’s manual, warranty manual,
infotainment manual, if applicable,
and zip lock bag or pouch.
Current and Past Models
Service manuals and customer
literature are available for many
current and past model year GM
vehicles.
To order, call 1-800-551-4123
Monday–Friday, 8:00 a.m.–6:00 p.m.
eastern time
For credit card orders only (VISA,
MasterCard, or Discover), see
Helm, Inc. at: www.helminc.com.
To order by mail, write to:
Helm, Incorporated
Attention: Customer Service
47911 Halyard Drive
Plymouth, MI 48170
Make checks payable in U.S. funds.
Radio Frequency
Statement
This vehicle has systems that
operate on a radio frequency that
complies with Part 15 of the Federal
Communications Commission (FCC)
rules. Operation is subject to the following
two conditions:
1. The device may not cause harmful interference.
2. The device must accept any interference received, including
interference that may cause
undesired operation of the
device.
Changes or modifications to any of
these systems by other than an
authorized service facility could void
authorization to use this equipment.

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