2026 Peterbilt 520 technical service bulletins

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

• Oct 29, 2026 Service bulletinAn upgraded power steering pump is available for certain Model 520 chassis with a RHSU or dual steering...
• Oct 28, 2026 Service bulletinThere is an update to the CARB Base Emissions Warranty Limits table and Manufacturer’s Warranty Coverage...
• Oct 23, 2026 Service bulletinEaton service bulletin TAIB-1026 instructs dealers to update the master switch module (MSM) software
• Oct 16, 2026 Service bulletinAdditional chassis have been added to the population
• Sep 11, 2026 Service bulletinKenworth: Dealers should check the chassis list and SIR weekly for VIN changes
• Sep 3, 2026 Service bulletinKW: The chassis list has been updated to include 1 chassis
• Aug 21, 2026 Service bulletinThis optional software update is expected to be available after 08/28/2026.
• Aug 19, 2026 Service bulletinPB: The chassis list has been updated to include 11 chassis
• Aug 13, 2026 Service bulletinWhen DAVIE version 26.21.2 is used to update the VECU3 to software version 3.4.46.0, the VECU3 5071...
• Aug 13, 2026 Service bulletinThis optional software update is expected to be available in late August 2026 for chassis equipped with...
• Aug 13, 2026 Service bulletinUpdated Sheppard Steering Gear Classification Tool link in Inspection Procedure
• Aug 13, 2026 Service bulletinKW -The chassis list has been updated to include 2 chassis
• Aug 1, 2026 Service bulletinThis optional software update is expected to be available on 08/07/26 for chassis equipped with EPA 2024...
• Jul 21, 2026 Service bulletinAn optional software update is expected to be available on or after 07/31/26 for chassis equipped with EPA...
• Jul 2, 2026 Service bulletinThere is an update to the Base Emissions Warranty Limits table [PR1.1]and general certification...
• Jul 2, 2026 Service campaignAdditional US chassis have been added, along with additional Canadian chassis under identical safety...
• Jun 30, 2026 Service campaignLeveraging PACCAR’s advanced Prognostic prediction algorithms, certain PACCAR MX-11 and MX-13 EMY...
• May 20, 2026 Service bulletin​Updated cross shaft and bearing installation steps have been added to the repair procedures.
• May 14, 2026 Service campaignCertain Peterbilt Model 520 BEV chassis with an Accelera Power Control and Accessory System (PCAS) were...
• Apr 10, 2026 EmissionsEMY25 Engine Label Replacement
• Apr 10, 2026 EmissionsKW Certain vehicle model year 2026 Kenworth chassis equipped with EMY2025 PACCAR MX engines require an...
• Apr 1, 2026 EmissionsEPA17-24 mx
• Feb 28, 2026 Service campaignKW: ​Certain Kenworth L770 chassis may have Right-Hand (RH) steering cross shaft bearing mounting holes...
• Feb 13, 2026 Service campaignBattery Electric Vehicle (BEV) de-energizing and re-energizing procedures have been added to the bulletin...
• Jan 30, 2026 Service bulletinCARB Label Procedure Update The repair procedure removes the aftermarket change request, adds GHG label...
• Dec 31, 2025 Service bulletinCertain Battery Electric Vehicles that are subject to California Air Resources Board (CARB) regulations...
• Dec 23, 2025 Service bulletinCertain Kenworth L770 and Peterbilt Model 520 chassis may encounter a slight increase in effort in the...
• Dec 23, 2025 Service bulletinParts and procedures are now available for all affected chassis equipped with Vehicle Electronic Control...
• Nov 4, 2025 Service bulletinRepair procedures and warranty information for model 520EV are now available
• Nov 4, 2025 Service bulletinRepair procedures and warranty information for model 520EV are now available
• Aug 1, 2025 Service campaignProcedures are now available for Phase 1 chassis equipped with Internal Combustion Engines (ICE) and...