Service bulletin 43-088
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.
| Type | Service bulletin |
|---|---|
| NHTSA id | 11034394 |
| Published by NHTSA | 2026-07-02 |
| Manufacturer's number | 43-088 |
| Manufacturer's date | 2026-06-29 |
| NHTSA component | ENGINE |
NHTSA's summary
"An optional software update will be available on 07/06/2026 for chassis equipped with EMY 2021B-2023PACCAR MX-11 and MX-13 engines. This update provides customers with additional time to service theirtrucks before a DEF-related derate occurs. The software is being offered to customers in alignment withrecently updated regulatory agency guidance."
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
| KENWORTH L770 | 2024, 2025 |
|---|---|
| KENWORTH T680 | 2020, 2021, 2022, 2023, 2024, 2025 |
| KENWORTH T880 | 2020, 2021, 2022, 2023, 2024, 2025 |
| KENWORTH W990 | 2020, 2021, 2022, 2023, 2024, 2025 |
| PETERBILT 365 | 2020, 2021, 2022, 2023, 2024, 2025 |
| PETERBILT 367 | 2020, 2021, 2022, 2023, 2024, 2025 |
| PETERBILT 389 | 2020, 2021, 2022, 2023, 2024, 2025 |
| PETERBILT 520 | 2020, 2021, 2022, 2023, 2024, 2025 |
| PETERBILT 567 | 2020, 2021, 2022, 2023, 2024, 2025 |
| PETERBILT 579 | 2020, 2021, 2022, 2023, 2024, 2025 |
Listing a model year does not mean every vehicle of it is concerned: the document says which.
| 23V749000 | 2023-11-07. ENGINE |
|---|---|
| 2022470 | 2022-08-18. Engine |
| 22V631000 | 2022-08-17. ENGINE AND ENGINE COOLING:ENGINE:ENGINE CONTROL MODULE (ECU/ECM) |
| 21V080000 | 2021-02-17. ENGINE |
| 19V282000 | 2019-04-09. ENGINE; ELECTRICAL SYSTEM |
A recall listed here may apply to some of the same vehicles. Only the manufacturer can say whether it applies to one vehicle.
| P001 | 2026-09-29. 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." |
|---|---|
| E343 | 2026-09-23. Service bulletin. An exhaust manifold slip joint seal kit is now available for EPA 2017-2024 PACCAR MX-13 engines. |
| P003 | 2026-09-23. Service bulletin. "KW: A link to the PACCAR Powertrain Prognostics Webcast has been added in the Links section. PB: The chassis list has been updated to include 1 chassis. The total chassis count is now 10. A link to the PACCAR Powertrain Prognostics Webcast has been added in the Links section." |
| P001 | 2026-09-23. 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." |
| P002 | 2026-09-23. Service bulletin. "KW: A link to the PACCAR Powertrain Prognostics Webcast has been added in the Links section. PB: The chassis list has been updated to include 2 chassis. The total chassis count is now 4. A link to the PACCAR Powertrain Prognostics Webcast has been added in the Links section." |
| P003 | 2026-08-27. Service bulletin. "KW: A link to the PACCAR Powertrain Prognostics Webcast has been added in the Links section. PB: The chassis list has been updated to include 1 chassis. The total chassis count is now 10. A link to the PACCAR Powertrain Prognostics Webcast has been added in the Links section." |
| P002 | 2026-08-27. Service bulletin. "KW: A link to the PACCAR Powertrain Prognostics Webcast has been added in the Links section. PB: The chassis list has been updated to include 2 chassis. The total chassis count is now 4. A link to the PACCAR Powertrain Prognostics Webcast has been added in the Links section." |
| P001 | 2026-08-27. 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." |
| 43-089 | 2026-08-25. Service bulletin. This optional software update is expected to be available after 08/28/2026. |
| P003 | 2026-08-25. Service bulletin. The PB chassis list has been updated to include 1 chassis. The total chassis count is now 9. |