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Service bulletin SB_406.12

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 id10240751
Published by NHTSA2023-08-17
Manufacturer's numberSB_406.12
Manufacturer's date2023-07-21
NHTSA componentENGINE AND ENGINE COOLING

NHTSA's summary

Identify options for dealing with multiple failure mode codes on various versions of DEF headers for 2016 and newer Cummins engines. This latest revision is to address production and service change from optical header 3539748 to ultrasonic header 3584091.

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

Engine

Vehicles listed
CUMMINS CUMMINS

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