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Service bulletins for the 2021 Kenworth T880

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.

66 on file from NHTSA, as of 2026-10-19.

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Only bulletins with component: Engine are shown. Show all

Bulletins, newest first
P0012026-09-29. 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."
E3432026-09-23. Service bulletin. ENGINE. An exhaust manifold slip joint seal kit is now available for EPA 2017-2024 PACCAR MX-13 engines.
43-0882026-08-20. Service bulletin. ENGINE. The procedure has been updated to include additional steps for verifying the software level on the vehicle electronic control unit (VECU2) and digital display (DD). Steps have also been added to the PACCAR Common Rail Injection 2 (PCI2) software verification.
43-0882026-07-23. Service bulletin. ENGINE. This optional software update is now available for chassis equipped with EMY 2021B-2023 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.
41-0292026-07-22. Service bulletin. ENGINE. Incorrect air filters may be inadvertently installed in certain chassis equipped with under-hood Donaldson air filter housings.
E3162026-07-21. Service bulletin. ENGINE. The Condition, Chassis Affected, Service Action, Warranty, and Procedure sections have been updated to include the latest prognostics bulletin verbiage.
43-0882026-07-21. Service bulletin. ENGINE. "The software is not yet available. The bulletin will be updated when more information is available."
43-0882026-07-02. Service bulletin. ENGINE. "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."
CE0302026-06-25. Warranty extension. ENGINE; POWER TRAIN. "KW & PB 14 fuel injector part numbers (seven for MX-11 and seven for MX-13 engines) have been added to this warranty policy."
E3112026-06-17. Service bulletin. ENGINE. The PACCAR Powertrain Prognostics Webcast video link has been removed. It will be included with updated information at a later date.
E3112026-06-03. Service bulletin. ENGINE. Kenworth - The Warranty section has been updated to include Peterbilt-specific SRT codes for cross-division repair filing.
41-0242026-05-20. Service bulletin. ENGINE. Procedures have been updated to include additional truck models in the service intervals table.
45-0702026-05-06. 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.
E3262026-05-06. 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.
E3352026-04-07. Emissions. ENGINE. Expiration Date Format Update - Certain EPA21 compliant PACCAR MX-13 engines were built with intake valve springs that could fail. This failure can cause significant damage to the engine. New intake valve springs will be installed.
41-0242026-04-07. 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.
E3262026-04-07. Emissions. ENGINE. EPA17-24 MX-13 Fuel Injector Connector - This bulletin has been revised to include EPA24 PACCAR MX-13 engines.
45-0702026-02-05. Service bulletin. ENGINE. Procedure pictures updated for clarity. When troubleshooting Cummins X15 fault codes 555 or 556, follow this additional testing, inspection, and documentation procedure to help identify the root cause of dusted engines. This is not a stand-alone process but must be used alongside Cummins troubleshooting steps. Cummins Quickserve will reference this bulletin for fault codes 555 or 556.
E3112025-09-03. Other. ENGINE; POWER TRAIN. Condition, Chassis Affected, and Warranty sections updated with the following verbiage “E311 must be flagged and open in Service Information Record (SIR) at the time of RO open date to qualify.” Also, “Through Standard Warranty or any applicable active Extended Warranty” verbiage was removed from Warranty section.
E2902023-07-05. Service bulletin. FUEL SYSTEM, GASOLINE; ENGINE AND ENGINE COOLING. FIX-AS-FAIL Updated procedures and claim filing information. EPA2021 injector cleaning is referenced in RMI for certain injector faults. Complete the procedures in E290. Refer to E300 for in-tank additive information
43-0722023-07-05. Service bulletin. ENGINE AND ENGINE COOLING:EXHAUST SYSTEM; ENGINE AND ENGINE COOLING. Certain chassis with Engine Model Year 2016-2021 PACCAR MX-11/MX-13, or EPA13 and EPA21 Cummins ISX12/ISX15/X15 engines that had a previously failed DEF sensor and with DEF sensor software disabled due to industry DEF sensor shortages will now be able to receive a replacement DEF sensor, DEF tank heater coolant control valve, and re-enabled DEF diagnostic software. Please note that chassis equipped with PACCAR PX engines will be eligible for this repair at a future date when software is available.
E2902023-04-04. Service bulletin. ENGINE AND ENGINE COOLING. FIX-AS-FAIL Updated procedures and claim filing information. EPA2021 injector cleaning is referenced in RMI for certain injector faults. Complete the procedures in E290. Refer to E300 for in-tank additive information
E3002023-04-04. Service bulletin. ENGINE AND ENGINE COOLING. PACCAR will reimburse customers for the local purchase of in-tank fuel additive for EPA2021 compliant MX engines. This is a one-time reimbursement. Only customers who have received E290 injector cleaning qualify for this reimbursement. See bulletin for limits and purchase tracking requirements.
03-087 (E295)2023-03-06. Service bulletin. FUEL SYSTEM, OTHER:FUEL FILTER; ENGINE AND ENGINE COOLING. Certain Model Year 2021-2024 chassis with PACCAR MX engines and optional fuel filter restriction virtual gauge may display incorrect restriction levels. The virtual gauge will be temporarily disabled until a revised sensor strategy is developed.
E3032023-02-06. Service bulletin. ENGINE AND ENGINE COOLING. This campaign is the final opportunity to replace the oil filter screw cap to reduce occurrences of broken bypass valve tabs. Broken oil valve tabs can cause oil flow obstruction to critical engine parts, resulting in serious engine damage. Customers that do not receive this repair may be responsible for progressive engine damage caused by broken oil bypass valve tabs.

The summaries are NHTSA's. Each bulletin's page links NHTSA's copy of the manufacturer's document.