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Emissions E339

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)
TypeEmissions
NHTSA id11032286
Published by NHTSA2026-05-06
Manufacturer's numberE339
Manufacturer's date2026-04-10
Campaign id or software versionE339
NHTSA componentENGINE

NHTSA's summary

EMY25 Engine Label Replacement - (KW) Certain vehicle model year 2026 Kenworth chassis equipped with EMY2025 PACCAR MX engines require a revised engine label update. (PB) Certain vehicle model year 2026 Peterbilt chassis equipped with EMY2025 PACCAR MX engines require a revised engine label update.

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
KENWORTH T8802026
PETERBILT 5202026
PETERBILT 5672026

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

Other bulletins for the same vehicles and component
P0012026-09-29. Service bulletin. "Kenworth: Dealers should check the chassis list and SIR weekly for VIN changes. 2 chassis added to the chassis list. Peterbilt: Dealers should check the chassis list and SIR weekly for VIN changes. 10 chassis added to the chassis list."
E3432026-09-23. Service bulletin. An exhaust manifold slip joint seal kit is now available for EPA 2017-2024 PACCAR MX-13 engines.
P0012026-09-23. Service bulletin. "KW: The chassis list has been updated to include 1 chassis. The total chassis count is now 53. A link to the PACCAR Powertrain Prognostics Webcast has been added in the Links section. PB: The chassis list has been updated to include 8 chassis. The total chassis count is now 130. A link to the PACCAR Powertrain Prognostics Webcast has been added in the Links section."
P0012026-08-27. Service bulletin. "KW: The chassis list has been updated to include 1 chassis. The total chassis count is now 53. A link to the PACCAR Powertrain Prognostics Webcast has been added in the Links section. PB: The chassis list has been updated to include 8 chassis. The total chassis count is now 130. A link to the PACCAR Powertrain Prognostics Webcast has been added in the Links section."
43-0892026-08-25. Service bulletin. This optional software update is expected to be available after 08/28/2026.
P0012026-08-25. Service bulletin. "PB: The chassis list has been updated to include 11 chassis. The total chassis count is now 122. KW: The chassis list has been updated to include 3 chassis. The total chassis count is now 52."
P0012026-08-20. Service bulletin. "KW -The chassis list has been updated to include 2 chassis. Total chassis count is now 49. PB - The chassis list has been updated to include10 chassis. The total chassis count is now 111."
43-0892026-08-20. Service bulletin. This optional software update is expected to be available in late August 2026 for chassis equipped with EPA 2024 EMY 2024-2026 PACCAR MX-11 and MX-13 engines. This bulletin will be updated when the software is ready. This update provides customers with additional time to service their trucks before a DEF-related derate occurs. The software is being offered to customers in alignment with recently updated regulatory agency guidance. The procedure document has also been updated for clarity.
43-0892026-08-20. Service bulletin. This optional software update is expected to be available in late August 2026 for chassis equipped with EPA 2024 EMY 2024-2026 PACCAR MX-11 and MX-13 engines. This bulletin will be updated when the software is ready. This update provides customers with additional time to service their trucks before a DEF-related derate occurs. The software is being offered to customers in alignment with recently updated regulatory agency guidance. The procedure document has also been updated for clarity.
43-0892026-08-01. Service bulletin. This optional software update is expected to be available on 08/07/26 for chassis equipped with EPA 2024 EMY 2024-2026 PACCAR MX-11 and MX-13 engines. This update provides customers with additional time to service their trucks before a DEF-related derate occurs. The software is being offered to customers in alignment with recently updated regulatory agency guidance.