WenmarOpen by Wenmar Pro

Service bulletins for the 2020 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.

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

Warranty extensions
CE0372026-05-06. FUEL/PROPULSION SYSTEM. KW & PB DEF Quality Sensor part number Q21-6127-001 for Cummins X15 engines has been added to this warranty policy.

A warranty extension may pay for a repair after the basic warranty has ended. Read the document for which vehicles and which repair it covers.

By type

By component

By topic

Bulletins, newest first
42-0702026-10-17. Service bulletin. UNKNOWN OR OTHER. Due to supplier constraints, an authorized aftermarket surge tank has been made available.
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.
E3112026-07-21. 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."
26-0352026-07-21. Service bulletin. POWER TRAIN. Updated Eaton's TAIB0885EN Bulletin link.
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."
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.
02-1772026-06-03. Service bulletin. ELECTRICAL SYSTEM. Troubleshooting procedures for 2.1m cab power windows are now available.
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.
CE0372026-05-06. Warranty extension. FUEL/PROPULSION SYSTEM. KW & PB DEF Quality Sensor part number Q21-6127-001 for Cummins X15 engines has been added to this warranty policy.
14-0342026-05-06. Service bulletin. UNKNOWN OR OTHER. Bogie Crossmember Torque Value Update - Procedure has been updated to correct torque values.
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.
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.
02-1742023-09-01. Service bulletin. ENGINE AND ENGINE COOLING; STRUCTURE; EQUIPMENT. Certain W990 hood-mounted engine air intake covers could loosen and rattle or separate from vehicle. New air intake covers are available with improved retention. Installation of new covers requires hood modification. Procedures are available for replacement of hood-mounted engine air intake covers.
02-1842023-09-01. Service bulletin. STRUCTURE. Certain W990 chassis may have hood hardware that could loosen. Additionally, some chassis may have hood rests that are too rigid causing excessive noise. Hood attaching hardware and hood rests will be replaced as necessary.
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.
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.