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Service bulletin P-1670

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 id10027951
Published by NHTSA2009-02-24
Manufacturer's numberP-1670
Manufacturer's date2008-09-18
NHTSA componentENGINE AND ENGINE COOLING:ENGINE:DIESEL

NHTSA's summary

MACK TRUCK: UNIT INJECTOR AND EXHAUST ROCKER ARMS, COMBUSTION SEALING WASHER AND UNIT INJECTOR YOKE REPLACEMENT. MODEL AND MODEL YEARS UNKNOWN. *PE

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

Vehicles listed
MACK CH1994

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

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