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Service bulletin TSB180025

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 id11018175
Published by NHTSA2025-05-08
Manufacturer's numberTSB180025
Manufacturer's date2025-04-26
NHTSA componentENGINE

NHTSA's summary

This Technical Service Bulletin describes the verification and resolution steps for the coolant thermostat which may exhibit a fatigue malfunction caused by internal pressure, resulting in fault codes 146, 151, 1962, 2646 or 2963 being set, excessive coolant temperature, or an inability for the engine to reach operating temperature. This is an update to a previously submitted communication.

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 ISL9
CUMMINS L9

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