CHEVROLET LOW CAB FORWARD 2020 Owner's 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
340 Service and Maintenance
UsageFluid/Lubricant
Engine Oil Engine oils with the letters CK-4 are required for your vehicle. The CK-4
designation can appear either alone or in combination with other American
Petroleum Institute (API) designations, such as API CK-4/SL. These letters
show API levels of quality. To determine the preferred viscosity for your
vehicle's diesel engine, see Engine Oil0235.
Hydraulic Brake Booster (If
Equipped) DEXRON
®-VI Automatic Transmission Fluid.
Power Steerig Fluid DEXRON
®-VI Automatic Transmission Fluid.
Rear Axle Multi purpose gear oil SAE80W-90 GL-5, SAE90 GL-5
Rear Axle
(Limited slip differential (LSD)) Multi purpose gear oil SAE80W-90 GL-5, SAE90 GL-5 for limited slip
differential together with limited slip differential lubricant additive (GM
Part No. 88900330) or equivalent.
Windshield Washer Solvent Automotive windshield washer fluid that meets regional freeze protection
requirements.

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 341
Be sure to use the LSD gear oil
additive mentioned above in
vehicles equipped with limited slip
differentials, and ensure there is an
appropriate amount of the LSD gear
oil additive, otherwise a chattering
noise and/or excessive vibration
may occur when turning.
If abnormal noises occur despite
having used the specified LSD gear
oil additive, have it inspected and
serviced at your dealer.Maintenance
Replacement Parts
Replacement Parts
Please contact your dealer for
genuine GM parts.
{Warning
If part replacement is necessary,
the part must be replaced with
one of the same part number or
with an equivalent part. Use of a
replacement part of lesser quality
may result in personal injury or
damage to 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
342 Service and Maintenance
5.2L Diesel
PartGM Part Number
Engine Air Cleaner 97780479
Engine Oil Filter 98298404
Fuel Filter: Engine Side 98147525
Fuel Filter: Chassis Side 98037481
Replacement Fasteners
During vehicle maintenance, any
fasteners used to replace older
ones must have the same
measurements and strength as
those removed, whether metric or
customary. Fasteners taken from
the vehicle should be saved for
reuse in the same location when
possible. Where a fastener cannot
be used again, take care to choose
a replacement that matches the old
one. For information and help, see
your dealer.{Warning
This vehicle is primarily
dimensioned in the metric system.
Most fasteners are metric and
many are very close in dimension
to well-known customary
fasteners in the inch system.
Mismatched or incorrect fasteners
can result in damage to the
vehicle or possibly personal
injury.

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 343
Technical Data
Vehicle Identification
Vehicle IdentificationNumber (VIN) . . . . . . . . . . . . . . . 343
Vehicle Data
Capacities andSpecifications . . . . . . . . . . . . . . . 349
Engine Drive Belt Routing . . . . 355
Vehicle Identification
Vehicle Identification
Number (VIN)
The VIN and engine number are
necessary for registering your
vehicle. They are also necessary
when your vehicle undergoes official
inspections. Provide your dealer
with these numbers when you are
having the vehicle repaired or when
ordering replacement parts. The
Dealer will be able to do the
requested jobs more competently
and quickly.
VIN and Weight Rating Plate

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
344 Technical Data
The "VIN, Weight Rating, and
Greenhouse Gas (GHG) Emissions
Plate" shows the manufacturer's
gross vehicle weight rating (GVWR),
the front and rear gross axle weight
ratings (GAWRs), as well as the VIN
and emissions information for your
vehicle.
This plate is located on the left side
rear pillar panel below the striker
(single cab) or on the left center
pillar panel beside the shoulder seat
belt anchor (crew cab).The VIN is a legal identifier of your
vehicle. It not only appears on the
VIN, Weight Rating, and
Greenhouse Gas (GHG) Emissions
plate; but also on the vehicle title
and registration. The VIN
specifically identifies a vehicle
by code.
See
“Overloading” underInformation
on Loading the Vehicle 046.
The VIN contains multiple pieces of
information including the vehicle
and engine model codes as shown
below.

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 345
J A L C 4 W 1 6 * L 7 K 0 0 0 0 11 2 3 4 5 6 7 8 9 10 11
Section Description
1 World Manufacturer Identifier (WMI) JAL: ISUZU
2 GVWR and Brake System C: 14,001-16,000 lbs. hydraulic brake system
E: 16,001-19,500 lbs. hydraulic brake system
3 Series Code 4: 4500HD/4500XD
5: 5500HD/5500XD
4 Cab Type Code W: Steel tilt single cab, 71 inch bumper to back of cab (BBC)
J: Non-tilt crew cab, 110 inch bumper to back of cab (BBC)
5 Chassis Type Code 1: 4 x 2
6 Engine Code 6: 4HK1
7 Check Digit
8 Model Year Code L: 2020

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
346 Technical Data
SectionDescription
9 Plant Code 7: Fujisawa
10 Model Code 0: 4500HD
3: 5500XD
9: 5500HD
K: 4500XD
11 Sequence Numbers
Interpretation of the VIN may differ
depending on the vehicle. For
further details, please ask your
dealer.
The engine number is stamped on
the right side front part of the engine
block.

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 347
Option Codes
The ID plate at the lower part of the
righthand door striker indicates
option codes. These codes are
three-digit, alphanumeric codes,
each assigned to a particular
component of the vehicle.You will be able to use these codes
to identify the model or type of
engine, transmission, rear axle or
other components when your
vehicle needs inspection and other
services.

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
348 Technical Data
OptionCodes Component
RJS 4HK1
Y6Q Transmission: Automatic transmission A465ID model 6CP Rear Axle: Heavy-duty 320mm G73 Rear Axle: Heavy-duty 292mm
7QQ Other Components: Hydraulic brake booster (HBB)
There are more option codes than
those indicated above. Depending
on the vehicle, an option code may
not be shown. For detailed
specifications of your vehicle, see
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
Technical Data 349
Vehicle Data
Capacities and Specifications
These specifications are given here for information only. Before using them, see the Cautions and other instructions
throughout this manual–the index may help you locate such items. For more information, see the Service Manual
covering the chassis or body part in question. Your dealer may also be able to help.
Engine Specifications
Description Water-cooled, overhead camshaft, direct injection engine with a charge air cooled
turbocharger.
Manufacturer Isuzu
Model 4HK1–5.2L Diesel Engine
Engine type Inline 4, Four Cycle
Induction Turbocharged W/Charge Air Cooler
Bore 115 mm
Stroke 125 mm
Displacement 5.193 L (317 CID)
Full load RPM 2,400 rpm
Compression ratio 16.5 to 1
Firing order 1-3-4-2
Fuel injection timing
(static) degree 0°