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Service bulletins for the 2026 Kenworth T680

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.

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

By type

By component

By topic

Bulletins, newest first
27-0122026-06-17. Service bulletin. POWER TRAIN. The attachment for Eaton bulletin TAIB-1015 has been updated to the latest version to improve process flow.
R26012026-06-04. Service bulletin. ELECTRICAL SYSTEM. Updated primary and/or secondary chassis modules for certain pre-production Kenworth chassis are now available for installation.
27-0122026-06-03. Service bulletin. POWER TRAIN. KW: A Transmission Control Module (TCM) software update is now available for certain T680, T880, and W990 chassis with Eaton Endurant transmissions, TCM software version R5.5 or later and an AT5 controller, where the TASPS fails. Please see the Eaton bulletin TAIB-1015 in the Attachments section for details. PB: A Transmission Control Module (TCM) software update is now available for certain Model 567, 579, and 589 chassis with Eaton Endurant transmissions, TCM software version R5.5 or later and an AT5 controller, where the TASPS fails. Please see the Eaton bulletin TAIB-1015 in the Attachments section for details.
T0242026-06-03. Service bulletin. POWER TRAIN. KW: A Transmission Control Module (TCM) software update is now available for certain T280, T380, T480, T680, T880, and W990 chassis with PACCAR TX-12 and TX-18 transmissions, TCM software version R5.5 or later and an AT5 controller, where the TASPS fails. PB: A Transmission Control Module (TCM) software update is now available for certain Model 537, 548, 567, 579, and 589 chassis with PACCAR TX-12 and TX-18 transmissions, TCM software version R5.5 or later and an AT5 controller, where the TASPS fails.
02-1772026-06-03. Service bulletin. ELECTRICAL SYSTEM. Troubleshooting procedures for 2.1m cab power windows are now available.
43-0872026-06-03. Service bulletin. UNKNOWN OR OTHER. (KW) Certain T680 / T800 / T880 / W900 / W990 have updated GHG labels available for order and installation.
41-0242026-05-20. Service bulletin. ENGINE. Procedures have been updated to include additional truck models in the service intervals table.
43-0872026-05-06. 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.
43-0872026-05-06. 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.
45-0702026-05-06. 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.
14-0342026-05-06. Service bulletin. UNKNOWN OR OTHER. Bogie Crossmember Torque Value Update - Procedure has been updated to correct torque values.
E3402026-05-06. Emissions. ENGINE. KW Certain vehicle model year 2026 Kenworth chassis equipped with EMY2025 PACCAR MX engines require an amended engine label. The engine label is now available for order and installation. PB Certain vehicle model year 2026 Peterbilt chassis equipped with EMY2025 PACCAR MX engines require an amended engine label. The engine label is now available for order and installation.
36-0102026-05-06. Service campaign. UNKNOWN OR OTHER; FORWARD COLLISION AVOIDANCE: ADAPTIVE CRUISE CONTROL. Bendix Fusion Camera Parameter Correction - (KW) Certain Kenworth T680 chassis may have certain software parameters out of specification. Certain out of specification parameters may result in customer dissatisfaction. (PB) Certain Peterbilt Model 579 chassis may have certain software parameters out of specification. Certain out of specification parameters may result in customer dissatisfaction.
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.
34-1002026-04-07. Service campaign. EXTERIOR LIGHTING. Halogen Headlamp Operation -Activating the Flash to Pass system on certain [Kenworth / Peterbilt] vehicles may cause one headlamp to deactivate.
37-0042026-04-07. Service campaign. UNKNOWN OR OTHER. PACCAR MX-13 VECU3 Software Update - Certain heavy-duty chassis equipped with a PACCAR MX-13 engine are eligible for a Vehicle Electronic Control Unit (VECU3) software update.
43-0832026-04-07. 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.
41-0242026-04-07. 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.
46-0242026-02-05. Service bulletin. UNKNOWN OR OTHER. CARB Label Procedure Update The repair procedure removes the aftermarket change request, adds GHG label inspection, and directs dealers to open a TCS365 case to order new labels. Warranty codes for inspection and label replacement have been updated. Certain Battery Electric Vehicles that are subject to California Air Resources Board (CARB) regulations have GHG labels that are missing the CARB Enhanced EV and FCEV Statement.
25PACF2026-01-06. 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.
46-0242026-01-06. Service bulletin. ELECTRICAL SYSTEM. Certain Battery Electric Vehicles that are subject to California Air Resources Board (CARB) regulations have Vehicle Emissions Control Information (VECI) labels that are missing the CARB Enhanced EV and FCEV Statement.
27-0112026-01-06. 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.
25PACG2025-11-05. Service bulletin. ELECTRICAL SYSTEM. The 15-inch digital display in certain model year 2024–2026 Kenworth chassis may enter recovery mode (blue wrench screen) without prior indication. The screen becomes non-responsive and may result in non-compliance with FMVSS/CMVSS 101 (Controls and Displays), 121 (Air Brake Systems), 136 (Electronic Stability Control Systems for Heavy Vehicles). Because of a loss of speedometer and other functionality such as warnings, indicators, and gauges, the driver will not see the truck speed or the warnings that appear on the digital display. A loss of information on the digital display may increase the risk of a crash.

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