# Service bulletin 4239

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.

- Type: Service bulletin
- NHTSA id: 616466
- Published by NHTSA: 2001\-02\-27
- Manufacturer's number: 4239
- Manufacturer's date: 2000\-09\-01
- NHTSA component: SERVICE BRAKES, HYDRAULIC:POWER ASSIST:VACUUM:HOSES, LINES/PIPING, AND FITTINGS

## NHTSA's summary

GENERAL INFORMATION STATING THAT VEHICLES WITH HYDRAULIC BRAKES CAN BE ORDERED WITH AN OPTIONAL AIR SUPPLY. THIS OPTION INCLUDES A SINGLE CHECK VALVE INSTALLED AT THE SUPPLY TANK TO PREVENT AIR FROM LEAKING BACK THROUGH THE COMPRESSOR WHEN THE VEHICLE IS PARKED AND THE ENGINE SHUT DOWN. THE VALVE IS INSTALLED ON VEHICLES BUILT AFTER MARCH 8, 1999, EXCEPT THOSE WITH A HOLSET COMPRESSOR OR OPTIONAL AIR DRYER. \*TT

## The document

No address for NHTSA's copy can be built for this communication. Ask the dealer for it by the manufacturer's number.

## Components

Brakes

## Vehicles listed

- FREIGHTLINER BUSINESS CLASS

JSON: [/v1/bulletins/616466](/v1/bulletins/616466)

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