Service bulletins for the 2026 Kenworth W990
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.
39 on file from NHTSA, as of 2026-10-19.
By type
By component
By topic
Only bulletins with component: Engine are shown. Show all
| P001 | 2026-09-29. Service bulletin. ENGINE. "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." |
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| E343 | 2026-09-23. Service bulletin. ENGINE. An exhaust manifold slip joint seal kit is now available for EPA 2017-2024 PACCAR MX-13 engines. |
| P001 | 2026-09-23. Service bulletin. ENGINE. "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." |
| P001 | 2026-08-27. Service bulletin. ENGINE. "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." |
| 43-089 | 2026-08-25. Service bulletin. ENGINE. This optional software update is expected to be available after 08/28/2026. |
| P001 | 2026-08-25. Service bulletin. ENGINE. "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." |
| P001 | 2026-08-20. Service bulletin. ENGINE. "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." |
| 43-089 | 2026-08-20. Service bulletin. ENGINE. 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. |
| 43-089 | 2026-08-01. Service bulletin. ENGINE. 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. |
| 43-089 | 2026-07-22. Service bulletin. ENGINE; ELECTRICAL SYSTEM. An optional software update is expected to be available on or after 07/31/26 for chassis equipped with EPA 2024 engine model year (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. |
| 41-029 | 2026-07-22. Service bulletin. ENGINE. Incorrect air filters may be inadvertently installed in certain chassis equipped with under-hood Donaldson air filter housings. |
| P001 | 2026-07-02. Service campaign. ENGINE. Leveraging PACCAR’s advanced Prognostic prediction algorithms, certain PACCAR MX-11 and MX-13 EMY 2024-2026 engines will receive proactive replacement instructions for the PM sensor to maximize uptime and maintain optimal performance. |
| 41-024 | 2026-05-20. Service bulletin. ENGINE. Procedures have been updated to include additional truck models in the service intervals table. |
| 43-087 | 2026-05-06. Emissions. ENGINE. EMY21-25 GHG Label Replacement (KW) Certain T680 / T800 / T880 / W900 / W990 have updated GHG labels available for order and installation. (PB) Certain Model 367 / 389 / 567 / 579 / 589 have updated GHG labels available for order and installation. |
| 45-070 | 2026-05-06. Service bulletin. ENGINE. The attached procedures document has been updated with more detail and explanations. This is not a stand-alone procedure. Cummins Quickserve troubleshooting will specify the use of these procedures while troubleshooting specific fault codes. |
| E326 | 2026-05-06. Emissions. ENGINE; ELECTRICAL SYSTEM. EPA17-24 MX Fuel Injector Connector - This bulletin has been revised to include all EPA17-24 and CARB24 PACCAR MX engines. |
| 41-024 | 2026-04-07. Service bulletin. ENGINE. Engine Air Filter Servicing UPDATE - Procedures are available to support the maintenance, service intervals, and intake system inspection process for all engine air intake system components. |
| E326 | 2026-04-07. Emissions. ENGINE. EPA17-24 MX-13 Fuel Injector Connector - This bulletin has been revised to include EPA24 PACCAR MX-13 engines. |
| 43085 | 2026-02-04. Service bulletin. ENGINE. Certain vehicle model year 2026 T880 / W900 / W990 chassis have updated GHG labels available for order and installation. |
The summaries are NHTSA's. Each bulletin's page links NHTSA's copy of the manufacturer's document.