2020 Kenworth T800 technical service bulletins

Bulletins tell dealers how to fix known problems. A warranty extension means the manufacturer pays for that repair for longer.

• Apr 17, 2026 Warranty extensionKw & pb DEF
• Oct 30, 2026 Service bulletinCertain chassis equipped with an engine model year 2019
• Oct 30, 2026 Service bulletinThis optional software update is expected to be available after 10/30/2026 for chassis equipped with EMY...
• Oct 13, 2026 Service bulletinDue to supplier constraints, an authorized aftermarket surge tank has been made available.
• Sep 11, 2026 Service bulletinKenworth: Dealers should check the chassis list and SIR weekly for VIN changes
• Jul 10, 2026 Service bulletinThe Condition, Chassis Affected, Service Action, Warranty, and Procedure sections have been updated to...
• Jun 6, 2026 Service bulletinThe PACCAR Powertrain Prognostics Webcast video link has been removed
• May 18, 2026 Service bulletinKenworth
• Apr 17, 2026 Service bulletinThe attached procedures document has been updated with more detail and explanations
• Apr 16, 2026 Service bulletinBogie Crossmember Torque Value Update
• Jan 31, 2026 Service bulletinProcedure pictures updated for clarity
• Aug 20, 2025 OtherCondition, Chassis Affected, and Warranty sections updated with the following verbiage “E311 must be...
• Apr 9, 2024 Service bulletinCertain C500/T440/T470/T660/T680/T800/T880/W900 chassis may have air tank reservoirs that do not meet air...
• Mar 1, 2024 Service bulletinSafety Recall Repair parts and procedures are now available
• Nov 28, 2023 Service bulletinSafety Recall Interim Notification On certain Kenworth model year 2018 through 2024 C500/T660/T800/W900...
• Jun 2, 2023 Service bulletinCertain chassis with Engine Model Year 2016-2021 PACCAR MX-11/MX-13, or EPA13 and EPA21 Cummins...
• Jan 12, 2023 Service bulletinThis campaign is the final opportunity to replace the oil filter screw cap to reduce occurrences of broken...
• Oct 18, 2022 Service bulletinInfo Only
• Aug 3, 2022 Service bulletinKenworth is providing guidance for PACCAR MX Engine Composite Oil Pan leak troubleshooting to avoid...
• May 10, 2022 Service bulletinSafety Recall – Interim Notification
• Sep 21, 2021 Service bulletinFix-As-Fail – Due to undersupply issues, only a limited supply of Diesel Exhaust Fluid (DEF) sensors are...
• Sep 20, 2021 Service bulletinInformation Only
• Jun 22, 2021 Service bulletinSafety Recall – Cummins Fuel Rail Leak – the federal safety agency ID: 21V391 / TC: 2021-323, Cummins...
• Feb 10, 2021 Service bulletinInformation Only – Windshield washer pumps have a high No Trouble Found rate
• Dec 18, 2020 Service bulletinFix-As-Fail
• Oct 12, 2020 Service bulletinFix-As-Fail – The Battery Management System (BMS) may report the incorrect battery condition
• Sep 25, 2020 Service bulletinInformation only: In 2020, Peterbilt and Kenworth began using the same M10, M12, M16, and M20 frame...
• Jul 21, 2020 Service bulletinNon-Safety Campaign – The end cap welds on certain fuel tanks may not meet internal quality standards due...
• Jun 8, 2020 Service bulletinInformation Only:
• Mar 17, 2020 Service bulletinInformation Only: Proper jump-starting voltage will eliminate high voltage related issues and equipment...
• Dec 18, 2019 Service bulletinInformation Only
• Nov 6, 2019 Service bulletinInformation Only:
• Sep 27, 2019 Service bulletinInformation Only –
• Jun 10, 2019 Service bulletinNon Safety Campaign: Holland Series FW17 fifth wheel handles may remain in an unlocked position when...
• May 3, 2019 Service bulletinNon-Safety Campaign