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Service bulletin 21PBE

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 id10198814
Published by NHTSA2021-07-06
Manufacturer's number21PBE
Manufacturer's date2021-06-30
NHTSA componentSERVICE BRAKES, AIR

NHTSA's summary

Safety Recall – TSE Brake Chamber Air Leak – NHTSA ID: 21V328. Meritor brake chambers were built with a misaligned park spring, which may cause a fatigue hole in the diaphragm and an internal air leak. The affected brake chambers will be replaced.

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 3482020
PETERBILT 5792020

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

Recalls for the same vehicles and component
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
34-0962023-05-05. Service bulletin. Fix As Fail – All New Model 579 chassis with Bendix radar opti on may have a harness rub against the radiator that is causing possible damage.
13-0602022-09-06. Service bulletin. The service information for Bendix Air Dryer maintenance is being updated to include new procedures.
13-0572022-04-05. Service bulletin. Fix-As-Fail – A hill start assist (HSA) valve plumbing revision eliminates ice buildup in the HSA valve exhaust in cold weather.
21PBM2022-01-06. Service bulletin. Safety Recall – Work Brake May Unintentionally Disengage – NHTSA ID: 21V906, TC: 2021-713. The work brake (also known as winch brake) may unintentionally disengage during winching operations, releasing the service brakes, increasing the risk of crash or injury. The VECU software will be updated to correctly set the speed interlock parameter.
13-0552020-11-05. Service bulletin. Fix as Fail: Peterbilt has introduced an improved mounting bracket for low mount air tanks for vehicles built between January 01, 2017 and July 06, 2020. Torsional vibration may stress the currently-installed brackets and cause them to fail near the bottom of the frame rail.
13-0542020-08-05. Service bulletin. Fix-As-Fail - Bendix New-Gen Lightweight Steer Axle Drum Brake Spider Cracking