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
| 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. |
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| 43-087 | 2026-05-06. Service bulletin. UNKNOWN OR OTHER. (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. |
| 14-034 | 2026-05-06. Service bulletin. UNKNOWN OR OTHER. Bogie Crossmember Torque Value Update - Procedure has been updated to correct torque values. |
| 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. |
| 34-100 | 2026-04-07. Service campaign. EXTERIOR LIGHTING. Halogen Headlamp Operation -Activating the Flash to Pass system on certain [Kenworth / Peterbilt] vehicles may cause one headlamp to deactivate. |
| 43-083 | 2026-04-07. Service bulletin. UNKNOWN OR OTHER. Exhaust Stack Isolators - Early wear of the polyurethane exhaust stack isolators may occur on certain Kenworth chassis due to excessive heat. Early wear of the polyurethane exhaust stack isolators may occur on certain Peterbilt chassis due to excessive heat. |
| 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. |
| 12-001 | 2026-02-04. Service bulletin. SUSPENSION. Vehicles equipped with Watson & Chalin 20K AL2200 lift axles may have crossmember fasteners of incorrect grade. |
| 25PACF | 2026-01-06. Service bulletin. EXTERIOR LIGHTING. Parts and procedures are now available for all affected chassis equipped with Vehicle Electronic Control Unit (VECU) part number Q21-1157-013-011 / Q21-1157-013-013 / Q21-1157-002-002 / Q21-1157-004-004 / Q21-1157-006-006 / Q21-1157-009-009. See attached Parts Matrix for required parts per chassis. |
| 27-011 | 2026-01-06. Service bulletin. POWER TRAIN. A transmission control module (TCM) software update is now available for certain T680 / T880 / W900 / W990 chassis with Eaton Endurant transmissions running TCM software version 5516372, where the PTO fails to operate or engage. Please see the attached Eaton bulletin TAIB- 1021 in the Attachments section of this bulletin for complete details. |
| 25PACF | 2025-09-03. Service campaign. EXTERIOR LIGHTING. Procedures are now available for Phase 1 chassis equipped with Internal Combustion Engines (ICE) and Vehicle Electronic Control Unit (VECU) part number Q21-1157-013-011 / Q21-1157-013-013. Parts and procedures for Phase 2 chassis will be available at a later date. This bulletin will be updated at that time. Please refer to the condition section for more details. Certain Ethernet Multiplexed Architecture (EMUX) chassis fail to conform to Federal and Canada Motor Vehicle Safety Standards (FMVSS/CMVSS) No. 108. Delayed or unsteady illumination of the vehicle’s stop lamps, reverse lamps, turn signal lamps and inadvertent change in headlamp illumination or lift axle position may" |
The summaries are NHTSA's. Each bulletin's page links NHTSA's copy of the manufacturer's document.