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Service bulletin FSB 257-003A

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 id10083634
Published by NHTSA2016-10-27
Manufacturer's numberFSB 257-003A
Manufacturer's date2015-10-30
NHTSA componentENGINE AND ENGINE COOLING:EXHAUST SYSTEM:EMISSION CONTROL:CRANKCASE (PCV)

NHTSA's summary

CRANKCASE VENTILATION TUBE HEATER. FOR CUSTOMER OPERATING VEHICLES IN EXTREME COLD TEMPERATURES, MACK TRUCKS HAS DEVELOPED A DEVICE THAT WILL PREVENT THE CRANKCASE VENTILATION (CCV) TUBE FROM BUILDING UP ICE AND FREEZING OVER WHICH COULD LEAD TO ENGINE DAMAGE.

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

Engine, Exhaust and emissions, Crankcase ventilation (PCV)

Vehicles listed
MACK MACK

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