2020 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 22, 2024 Warranty extension7/700 Service Agreement
• Oct 30, 2026 Service bulletinThis optional software update is expected to be available after 10/30/2026 for chassis equipped with EMY...
• Oct 29, 2026 Service bulletinAn upgraded power steering pump is available for certain Model 520 chassis with a RHSU or dual steering...
• Sep 11, 2026 Service bulletinKenworth: Dealers should check the chassis list and SIR weekly for VIN changes
• Aug 13, 2026 Service bulletinThe procedure has been updated to include additional steps for verifying the software level on the vehicle...
• Jul 21, 2026 Service bulletinThis optional software update is now available for chassis equipped with EMY 2021B-2023 PACCAR MX-11 and...
• Jul 7, 2026 Service bulletinThe software is not yet available
• Jun 29, 2026 Service bulletinAn optional software update will be available on 07/06/2026 for chassis equipped with EMY 2021B-2023PACCAR...
• Apr 1, 2026 EmissionsEPA17-24 mx
• May 31, 2025 Service bulletin5/29/2025: A new Ethernet Multiplexed Architecture (EMUX) Service Tool Kit service manual (SM034-022) has...
• Apr 30, 2025 Service campaign4/29/2025
• Nov 22, 2024 Service bulletinInfo Only Unnecessary starter replacements can result from customer complaints regarding engine starting...
• Sep 19, 2024 Service bulletinInformation Only Storage guideline procedures are now available for both Medium Duty and Heavy-Duty...
• Sep 14, 2024 Service campaignInformation Only New diagnostic tool is required to support PACCAR Ethernet Multiplexed Architecture...
• Jul 30, 2024 Service bulletinFix As Fail The height control valve (HCV) rod on vehicles with low air leaf suspensions is prone to...
• Jul 14, 2023 Service bulletinQuality and Volume Validation vehicles built for the 520 VMUX program between July 2019 and December 2020...
• Oct 18, 2022 Service bulletinInfo Only
• Aug 3, 2022 Service bulletinThe service information for Bendix Air Dryer maintenance is being updated to include new procedures.
• Jul 12, 2022 Service bulletinInfo Only – Certain 520 model chassis built between 2014 and 2021, and equipped with the Red Dot HVAC...
• Feb 4, 2022 Service bulletinDue to major data carriers phasing out 3G networks, chassis currently utilizing first generation Peoplenet...
• Jan 10, 2022 Service bulletinRetrofit
• Sep 23, 2021 Service bulletin​Safety Recall – Certain Model 520 trucks may have been built without a quick release (QR) valve
• Sep 21, 2021 Service bulletinFix-As-Fail – Due to undersupply issues, only a limited supply of Diesel Exhaust Fluid (DEF) sensors are...
• Jun 22, 2021 Service bulletinSafety Recall – Cummins Fuel Rail Leak – the federal safety agency ID: 21V391 / TC: 2021-323, Cummins...
• Jun 21, 2021 Service bulletin​Fix-As-Fail – PX9 oil pan may leak due to improper hardware
• Feb 25, 2021 Service bulletinThe current chassis harness connector contains a wire that is no longer necessary with the latest...
• Feb 10, 2021 Service bulletinInformation Only – Windshield washer pumps have a high No Trouble Found rate
• Dec 2, 2020 Service bulletinSafety Recall: Interim Dealer Notification
• Oct 1, 2020 Service bulletinFix as Fail: Peterbilt has introduced an improved mounting bracket for low mount air tanks for vehicles...
• Sep 25, 2020 Service bulletinInformation only: In 2020, Peterbilt and Kenworth began using the same M10, M12, M16, and M20 frame...
• Sep 16, 2020 Service bulletinPower train
• Aug 8, 2020 Service bulletinSafety Recall: Model 520 vehicles with Right-Hand Stand-Up (“RHSU”) configuration built between February...
• Jul 29, 2020 Service bulletinFix-As-Fail
• Jun 10, 2020 Service bulletinElectrical system
• Jun 10, 2020 Service bulletinFix as Fail: For all conventional models, except 387/587, equipped with Side-of-Cab (“SOC”) exhaust and...
• Jun 8, 2020 Service bulletinInformation Only:
• May 29, 2020 Service bulletinInformation only: Hendrickson Softek front axle maintenance intervals and requirements.
• Mar 24, 2020 Service bulletinService brakes, air: supply: quick release valve
• Mar 17, 2020 Service bulletinInformation Only: Proper jump-starting voltage will eliminate high voltage related issues and equipment...
• Mar 3, 2020 Service bulletinSteering
• Jan 31, 2020 Service bulletinSafety Related Campaign
• Dec 20, 2019 Service bulletinPower train
• Dec 18, 2019 Service bulletinInformation Only
• Nov 22, 2019 Service bulletinInformation only: Some model 320 and 520 vehicles built before 3/11/2019 may experience loss or loosening...
• Nov 6, 2019 Service bulletinInformation Only:
• Sep 27, 2019 Service bulletinInformation Only –
• Aug 28, 2019 Service bulletinFix-As-Fail -“ Composite fittings used in the cooling system may crack, resulting in coolant leaks
• Aug 23, 2019 Service bulletinFix-As-Fail: Two separate causes have been identified as root
• Jul 19, 2019 Service bulletinSafety Recall: Vehicles fail to confirm with FMVSS/CMVSS No 108 Table 1-a requirements which requires 2...
• Jun 10, 2019 Service bulletinInformation Only
• May 31, 2019 Service bulletinSafety Recall: INTERIM NOTIFICATION
• Apr 8, 2019 Service bulletinInformation Only: Proper instructions for closure of power distribution box cover to prevent corrosion.
• Apr 4, 2019 Service bulletinNon Safety Campaign: Vehicles were built with a 5 bolt supply wire for the air dryer pressure sensor that...