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Service bulletin 23PBJ

A bulletin is a manufacturer's communication to its dealers, as NHTSA indexes it. The summary is NHTSA's. The document is the manufacturer's: read it at NHTSA. A bulletin is not a recall, and listing a model year does not mean every vehicle of it is concerned.

The communication, as NHTSA indexes it (as of 2026-10-19)
TypeService bulletin
NHTSA id10248328
Published by NHTSA2024-01-05
Manufacturer's number23PBJ
Manufacturer's date2023-12-22
NHTSA componentSERVICE BRAKES, AIR

NHTSA's summary

Certain 536, 537, 548, and 567 chassis built with 2.1m Medium Duty End of Frame Trailer Connections and Tractor Protection Valves may not meet the standard trailer brake release timing requirements by 0.5 seconds. A delay in the trailer brake release may create momentary instability to the trailer and increase the risk of a crash.

The document

The document is the manufacturer's. This site does not hold it. NHTSA files a document at one of these two addresses; we have not asked NHTSA which.

Components

Brakes

Vehicles listed
PETERBILT 5362020 to 2021
PETERBILT 5362022, 2023, 2024
PETERBILT 5372020 to 2022
PETERBILT 5372023, 2024
PETERBILT 5482020 to 2023
PETERBILT 5482024

Listing a model year does not mean every vehicle of it is concerned: the document says which.

Recalls for the same vehicles and component
24V9150002024-12-09. ELECTRICAL SYSTEM:SOFTWARE; SERVICE BRAKES, HYDRAULIC:ANTILOCK/TRACTION CONTROL/ELECTRONIC LIMITED SLIP:CONTROL UNIT/MODULE
23V6610002023-09-29. SERVICE BRAKES, AIR
20230702023-02-15. Brakes
23V0870002023-02-15. SERVICE BRAKES, AIR
21V9060002021-11-19. ELECTRICAL SYSTEM:SOFTWARE; SERVICE BRAKES, AIR

A recall listed here may apply to some of the same vehicles. Only the manufacturer can say whether it applies to one vehicle.

Other bulletins for the same vehicles and component
25PBE2025-09-03. Service campaign. Parts and repair procedures are now available. Certain chassis may have a rear suspension tracking rod that interferes with the left rear brake valve components during full suspension travel. This interference could cause a loss of the rear service brake or ABS modulation for one rear axle wheel end, increasing the risk of a crash.
13-0652024-11-05. Service bulletin. 13-065 DAVIE4 Chassis Air Leak Testing Info Only A new test is now available in DAVIE4 to properly measure chassis air system pressure decay, provide test results, and pass/fail criteria. Your DAVIE tool must be at version 24.05 or newer for the test to be available. A test procedure document has also been made available that shows all necessary setup and testing procedure criteria (procedure document attached in Links section). The DAVIE4 “Check the air pressure decay rate” test and the test procedure document MUST be followed anytime a chassis comes in for a warranty related air system repair where excessive air system pressure decay is suspected. Warranty claims filed for air system pressure decay may be denied if DAVIE4 test AND test procedure have not been followed.
23PBJ2023-11-10. Service bulletin. Certain 536, 537, and 548 chassis built with 2.1m Medium Duty End of Frame Trailer Connections may exceed the standard trailer brake release timing requirements by 0.5 seconds due to the size of the tractor protection valve fitting and hose. A delay in the trailer brake release can create instability to the trailer and increase the risk of a crash.
23PBB2023-06-03. Service bulletin. Safety Recall The brake pedal plunger which connects the brake pedal to the brake valve may dislodge after the pedal is fully depressed, and rapidly released (side slip foot brake release). If the plunger in the brake pedal assembly dislodges the driver may be unable to apply the service brakes, which may increase the risk of a crash.
13-0602022-09-06. Service bulletin. The service information for Bendix Air Dryer maintenance is being updated to include new procedures.
13-0592022-03-04. Service bulletin. On certain Model Year 2022 chassis with manual transmissions, the optional “audible alarm when door is open and park brake is not set” feature operates incorrectly due to a software issue. Software will be corrected when available.