2023 Peterbilt 520 problems, complaints & recalls
Safety recalls (5)
Electrical System:propulsion System 2025-03-24 · campaign 25V181000 · 238 vehicles
Defect: PACCAR Incorporated (PACCAR) is recalling certain 2022-2025 Peterbilt 520, 579, and 2021-2025 Kenworth T680 trucks. The high voltage (HV) contactors may open, causing a sudden loss of high voltage and a loss of drive power.
Risk: A loss of drive power increases the risk of a crash.
Fix: Dealers will update the software and replace the electrical harness, free of charge. Owner notification letters were mailed May 13, 2025. Owners may contact Peterbilt's customer service at 1-940-591-4220 and Kenworth's customer service at 1-425-828-5888. PACCAR's numbers for this recall are 25PBC and 25KWC.
Electrical System:software 2024-12-09 · campaign 24V915000 · 220,764 vehicles
Defect: PACCAR Incorporated (PACCAR) is recalling certain 2021-2025 Peterbilt and Kenworth vehicles, equipped with Bendix EC80 Advanced Electronic Control Units (ECU). Please see the recall report for a complete list of models. Electrical noise and low signal to the power line carrier may cause the ECU to incorrectly process commands or stop functioning.
Risk: Safety systems that depend on the ECU (Automatic Traction Control, ABS, Electronic Stability Control, Active Cruise Control, and Collison Mitigation System) may not function properly or at all, increasing the risk of a crash.
Fix: Dealers will reprogram the ECU software, free of charge. Owner notification letters were mailed February 3, 2025. Owners may contact Kenworth's customer service at 1-425-828-5888 and Peterbilt's customer service at 1-940-591-4220. PACCAR's numbers for this recall are 24KWL and 24PBL.
Suspension:multiple Axle 2022-12-16 · campaign 22V939000 · 15,658 vehicles
Defect: PACCAR Incorporated (PACCAR) is recalling certain 2015-2023 Peterbilt 320 and 520 refuse trucks equipped with Haulmaax/EX suspensions. The suspension tracking rod brackets may fail and detach from the forward drive axle, causing the axle to become unstable.
Risk: An unstable axle can decrease vehicle stability and control, increasing the risk of a crash.
Fix: Dealers will inspect the welds and add an additional bracket between the tracking rod bracket and axle housing, as necessary, free of charge. Owner notification letters are expected to be mailed February 14, 2023. Owners may contact Peterbilt's customer service at 1-940-591-4220. PACCAR's number for this recall is 22PBL.
Engine And Engine Cooling:engine:engine Control Module (Ecu/Ecm) 2022-08-17 · campaign 22V631000 · 1,601 vehicles
Defect: PACCAR Incorporated (PACCAR) is recalling certain 2023 Peterbilt 220, 389, 520, 536, 537, 348, 367, 567, 548, 579, and 2023 Kenworth T680, K270, T440, T880, W990, K370, T280, T380, T480, T800, and W900 vehicles. The engine control module (ECM) may experience an internal electrical short-circuit, causing the engine to stall.
Risk: An unexpected engine stall can increase the risk of a crash.
Fix: Dealers will replace the ECM, free of charge. Owner notification letters are expected to be mailed October 16, 2022. Owners may contact Kenworth's customer service at 1-425-828-5888 and Peterbilt's customer service at 1-940-591-4220. PACCAR's number for this recall is 22KWG and 22PBG.
Steering 2022-07-28 · campaign 22V547000 · 47,500 vehicles
Defect: PACCAR Incorporated (PACCAR) is recalling certain 2022-2023 Kenworth T170, T270, T280, T370, T380, T440, T470, T480, T680, T800, T880, W900, W990, C500, and 2022-2023 Peterbilt 325, 330, 337, 348, 365, 367, 389, 520, 536, 537, 548, 567, and 579 vehicles. The steering gears may have been assembled incorrectly, which can cause the gears to fracture.
Risk: A fractured steering gear can cause a loss of steering control, increasing the risk of a crash.
Fix: Dealers will inspect the steering gear serial numbers, and replace the steering gears as necessary, free of charge. Owner notification letters were mailed September 26, 2022. Owners may contact Kenworth's customer service at 1-425-828-5888 and Peterbilt's customer service at 1-940-591-4220. PACCAR's numbers for this recall are 22PBE and 22KWE.
Service bulletins (49)
Technical service bulletins are repair instructions manufacturers send dealers for known issues. Unlike recalls, the fix is not automatically free — but naming the bulletin at the service desk can save diagnosis time and support goodwill repairs.
Engine 2026-09-11 · P001 · Service Bulletin/Repair Instructions
"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."
Forward Collision Avoidance: Warnings 2026-08-13 · 24KWL/PBL · Service Bulletin/Repair Instructions
the verbiage in the introduction section has been updated.
Engine 2026-08-13 · 43-088 · Service Bulletin/Repair Instructions
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.
Unknown Or Other 2026-07-22 · 46-020 · Service Bulletin/Repair Instructions
certain unaffected chassis have been removed from the chassis population.
Engine 2026-07-21 · 43-088 · Service Bulletin/Repair Instructions
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 recentl
Engine 2026-07-10 · E318 · Service Bulletin/Repair Instructions
the condition, chassis affected, service action, warranty, and procedure sections have been updated to include the latest prognostics bulletin verbiage. the warranty section has also been updated to include peterbilt specific srt codes for filing cross-division repairs.
Showing the 6 most recent of 49 bulletins. Search all of them free at nhtsa.gov.
What owners report
No detailed complaint narratives on file.
Excerpts of consumer complaints filed with NHTSA, lightly truncated. They are owner statements, not verified findings.