2020 CHEVROLET LOW CAB FORWARD service

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 339
Recommended Fluids, Lubricants, and Parts
Recommended Fluids and Lubricants
Fluids and lubricants identified below by name, part number, or specification can be obtained from your dealer.Usage Fluid/Lubricant
Automatic Transmission Automatic Transmission Fluid (GM Part No. 19354076).
Battery Terminals Petroleum Jelly (outer surfaces)
Brake Fluid DOT 3 Hydraulic Brake Fluid (GM Part No. 19353126).
Cab-Door Hinges and Latches
Lubricant Multi-Purpose Lubricant, Superlube (GM Part No. 12346241) or equivalent
containing zinc oxide.
Chassis Lubricant Chassis Lubricant (GM Part No. 12377985) or high temperature equivalent.
Diesel Exhaust Fluid (DEF) Diesel Exhaust Fluid (GM Part No. 19353126) or diesel exhaust fluid that meets ISO 22241-1 or displays the API Diesel Exhaust Fluid
Certification Mark.
Driveshaft Center Bearing, Wheel
Hub Bearing Lubricant NLGI #2 or #3
Driveshaft, Universal Joints and
Sliding Sleeve Lubricant NLGI #1 or #2 multi-purpose type grease
Engine Coolant 50/50 mixture of clean, drinkable water and GM extended life coolant. (GM Part No. 12378560) SeeEngine Coolant0243.

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 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
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°

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 351
Service SpecificationsWeights
Axle weight rating : Front 4500HD: 2431 kg (5,360 lb) 4500XD: 3007 kg (6,630 lb)
5500HD: 3098 kg (6,830 lb) 5500XD: 3300 kg (7,275 lb)
Engine Oil
Engine oil capacity When changing oil and filter: 11.0 L (11.6 qt)
*1
Engine Cooling System
Capacity 19.6 L (20.7 qt)
Engine oil Thermostat:
Starts to open 82–85 °C (180–185 °F)
Radiator pressure 108 kPa (16 psi) Transmission
Transmission oil capacity 13.7 L (28.9 pt)
*3
Rear Axle
Differential gear oil
capacity 4500HD/4500XD:
9.0 L (19.0 pt)
*4
5500HD/5500XD:10.0 L (21.1 pt)*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
Technical Data 353
Disc Brakes
Model 4500HD 4500XD/5500HD/5500XD
Brake size (Diameter x
Thickness) φ293 x 40 mm (φ11.54 x 1.57 in)
φ363 x 42 mm (φ14.29 x 1.65 in)
Rotor thickness [Standard Value] 40.0 mm (1.575 in) 42.0 mm (1.654 in)
[Usable Limit] 37.0 mm (1.457 in) 39.0 mm (1.535 in)
Pad thickness [Standard Value] 13.0 mm (0.512 in) 13.0 mm (0.512 in)
[Usable Limit] 1.0 mm (0.04 in) 1.0 mm (0.04 in) Service Brakes
Brake pedal free play 4500HD/4500XD 5–10 mm (0.20–0.39 in)
5500HD/5500XD 5–10 mm (0.20–0.39 in)
Clearance between the brake pedal and the brake pedal bracket with a pressure of 490 Y(50 kgf/110 lb ft)
applied to the brake pedal
4500HD/4500XD models 35 mm (1.38 in) or more
Clearance between the brake pedal and the brake pedal bracket with a pressure of 294 Y(30 kgf/66 lb ft) applied
to the brake pedal
5500HD/5500XD models 35 mm (1.38 in) or more