Complaints over time
Complaints about the 2020 Peterbilt 520 peaked in 2021, with 3 filed
Owner complaints about this model year, by the year they were filed with NHTSA.
Source: NHTSA ODI complaints file. The lighter column runs through October.
Model year
2020 Peterbilt 520
Truck, diesel, 4x2, built in Mexico. Owner complaints on file from Aug 2, 2021 to Aug 2, 2021.
Recall campaigns covering this model year1242k vehicles or units across those campaigns
Owner complaints33.0 times the median 2020 truck
Severity index0.02020 trucks average 3.5
First 24 months3Complaints in its first two years
Components
100% of complaints about the 2020 Peterbilt 520 name brakes
Owner complaints by component. Hover or focus a bar for the crash, fire, injury or death count.
Source: NHTSA ODI complaints file. A complaint can name more than one component; it is counted under the first.
Recalls
12 recall campaigns cover the 2020 Peterbilt 520
Check a specific vehicle by VIN on NHTSA's site: a campaign may cover only part of a model year's production.
| Campaign | Filed | Subject | Component | Vehicles | Remedy |
|---|---|---|---|---|---|
| 22V-939 | Dec 16, 2022 | Suspension tracking rod brackets may fail and detach from the forward drive axle, causing the axle to become unstable | Suspension | 15,658 | Repair or modification |
| 22V-277 | Apr 25, 2022 | Dana D-Series axle steer arm fasteners that attach the steering arm to the steering knuckle may fail | Steering | 17,641 | Part replacement |
| 21V-720 | Sep 16, 2021 | Quick release valve on the rear brake signal hose may be missing | Brakes | 15 | Repair or modification |
| 21V-391 | May 26, 2021 | Sealing washer may not seat correctly in the pilot bore holes, allowing the high pressure fuel rail assembly to leak | Fuel system | 612 | Part replacement |
| 21V-004 | Jan 11, 2021 | Steering column support structure may crack or break in certain right-hand, stand-up drive models | Steering | 1,021 | Part replacement |
| 20V-739 | Nov 25, 2020 | Stability control brake relay may have the Spring Brake Modulating (SBM) Valve or the lift axle hose incorrectly connected | Stability and traction control | 11 | Inspection |
| 20V-506 | Aug 26, 2020 | Axles may have lower rear pivot bolts that are not long enough to sufficiently engage the locking feature of the corresponding nuts | Powertrain | 1,097 | Part replacement |
| 20V-429 | Jul 24, 2020 | Incorrect bolts may have been used to secure the steering assist cylinder bracket, possibly allowing the bolts to loosen | Steering | 239 | Part replacement |
| 20V-132 | Mar 4, 2020 | Rear brake signal hose may be missing a quick release valve, possibly causing a delay in their brake release timing | Brakes | 233 | Repair or modification |
| 19V-911 | Dec 19, 2019 | Forward rear axle output shafts may have been improperly heat treated during manufacturing, possibly resulting in the shafts fracturing | Powertrain | 148 | Part replacement |
| 19V-452 | Jun 14, 2019 | Turn signals may also light up with the stop/tail lights when the brakes are applied | Lighting | 343 | Repair or modification |
| 19V-282 | Apr 9, 2019 | Due to undersized wires, the connector between the cab power harness and the power distribution center (PDC) harness may overheat and melt,… | Electrical system | 5,051 | Part replacement |
Source: NHTSA ODI recalls file.
Owner complaints
What owners reported about the 2020 Peterbilt 520
The full text of every complaint filed with NHTSA about this model year, newest first. Complaints are filed by owners and are not verified by NHTSA; NHTSA removes personal details before publishing.
3 complaints on file, page 1 of 1.
- Filed Aug 2, 2021Failure May 13, 2021Hays, KSService brakes
This one was taken in after the first one also for inspection by dealer. Issue wasn't as severe due to lower mileage and use. I believe the pads were just changed as a precaution, I don't believe they had started to separate.
NHTSA complaint 11427424 - Filed Aug 2, 2021Failure Apr 12, 2021Hays, KSService brakes
After issue with first truck dealership asked to bring in others to be inspected and found same issue with them. Front brake pads were separating from backing. This truck had less mileage so damage not as severe.
NHTSA complaint 11427422 - Filed Aug 2, 2021Failure May 6, 2021Hays, KSService brakes
Truck was brought in because driver heard a grinding noise. Mechanic inspected and found that the front disc brake pads and separated from the backing. Truck was thought to still be under warranty and was then taken to dealership for repairs.
NHTSA complaint 11427420
Source: NHTSA ODI complaints file.
Investigations
NHTSA has not opened an investigation on this model year
Source: NHTSA ODI investigations file.
Service bulletins
51 manufacturer communications cover this model year
Technical service bulletins and other notices the manufacturer sent to dealers. A bulletin is not a recall.
- P001 Sep 11, 2026 · 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." - 43-088 Aug 13, 2026 · 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. - 43-088 Jul 21, 2026 · 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 off… - 43-088 Jul 7, 2026 · Service Bulletin/Repair Instructions
"The software is not yet available. The bulletin will be updated when more information is available." - 43-088 Jun 29, 2026 · Service Bulletin/Repair Instructions
"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 … - E326 Apr 1, 2026 · Emissions
EPA17-24 MX Fuel Injector Connector - This bulletin has been revised to include all EPA17-24 and CARB24 PACCAR MX engines. - 98-030 May 31, 2025 · Service Bulletin/Repair Instructions
5/29/2025: A new Ethernet Multiplexed Architecture (EMUX) Service Tool Kit service manual (SM034-022) has been released to provide general use information. The new EMUX Service Tool Kit improves cab & chassis electrical troubleshooting efficiency, while red… - 46-016 Apr 30, 2025 · Service Campaign
4/29/2025: Campaign A software update is available for 520EV and 579EV Battery Electric Vehicles. This software update corrects or improves certain functions. Software update procedures have been revised. Campaign start date is 12/05/2024. Campaign A sof… - 32-025 Nov 22, 2024 · Service Bulletin/Repair Instructions
Info Only Unnecessary starter replacements can result from customer complaints regarding engine starting issues. A new Starter Troubleshooting Guide has been created to provide a comprehensive list of starting system checks, which should reduce unnecessary… - 7-700 Oct 22, 2024 · Warranty Program/Extension
7/700 Service Agreement - Letter Only. - 98-030 Sep 14, 2024 · Service Campaign
Information Only New diagnostic tool is required to support PACCAR Ethernet Multiplexed Architecture (EMUX). The EMUX Service Tool Kit will help improve cab & chassis electrical troubleshooting efficiency, while reducing the risk of component damage. - 46-014 Sep 19, 2024 · Service Bulletin/Repair Instructions
Information Only Storage guideline procedures are now available for both Medium Duty and Heavy-Duty Battery Electric Vehicles. - 16-044 Jul 30, 2024 · Service Bulletin/Repair Instructions
Fix As Fail The height control valve (HCV) rod on vehicles with low air leaf suspensions is prone to toggling over center during rough road conditions. With full suspension articulation, HCV bracket flexes and toggles over center the HCV linkage, which res… - R2304 Jul 14, 2023 · Service Bulletin/Repair Instructions
Quality and Volume Validation vehicles built for the 520 VMUX program between July 2019 and December 2020 are eligible for a retrofit of the digital display to a production intent unit that features updated base software, secured hardware, and the ability t… - 45-064 Oct 18, 2022 · Service Bulletin/Repair Instructions
Info Only - PACCAR is introducing Over-the-Air (OTA) software updates for engine MY17 and newer chassis equipped with Cummins X15, X12, ISX12, ISX12N, L9N, PX-7, and PX-9 engines The technology will leverage the existing Remote Diagnostic cs hardware to del… - 13-060 Aug 3, 2022 · Service Bulletin/Repair Instructions
The service information for Bendix Air Dryer maintenance is being updated to include new procedures. - 01-085 Jul 12, 2022 · Service Bulletin/Repair Instructions
Info Only – Certain 520 model chassis built between 2014 and 2021, and equipped with the Red Dot HVAC system, may have service port spacing which will not allow the connection of a pressure gauge to both the high and low side service ports simultaneously. … - 51-013 Feb 4, 2022 · Service Bulletin/Repair Instructions
Due to major data carriers phasing out 3G networks, chassis currently utilizing first generation Peoplenet Mobile Gateway (PMG001) will experience severe 3G service degradation as early as January of 2022. Chassis currently utilizing 3G antennas as a primar… - R2103 Jan 10, 2022 · Service Bulletin/Repair Instructions
Retrofit - The emissions exemption will be expiring on 5/15/2022 for certain pre-production vehicles equipped with PACCAR MX-11 and MX-13 EPA 2021 Emissions engines. Production-level components are now available to make these vehicles compliant. - 43-071 Sep 21, 2021 · Service Bulletin/Repair Instructions
Fix-As-Fail – Due to undersupply issues, only a limited supply of Diesel Exhaust Fluid (DEF) sensors are available. As a temporary solution, after PACCAR confirms a DEF sensor is not available, a temporary software update will allow a vehicle to continue op… - 21 PBK Sep 23, 2021 · Service Bulletin/Repair Instructions
Safety Recall – Certain Model 520 trucks may have been built without a quick release (QR) valve. The absence of this valve could affect rear brake timing on certain vehicles equipped with a tri-drive or liftable tag axle and Dual Seated or Right Hand Stand… - 45-062 Jun 21, 2021 · Service Bulletin/Repair Instructions
Fix-As-Fail – PX9 oil pan may leak due to improper hardware. Revised hardware will resolve the leak. - 21-PBD Jun 22, 2021 · Service Bulletin/Repair Instructions
Safety Recall – Cummins Fuel Rail Leak – NHTSA ID: 21V391 / TC: 2021-323, Cummins Recall: C2423. Cummins PX9 and ISX12 fuel rails may leak around a sealing washer, potentially resulting in fuel leaks. Undetected prolonged diesel fuel spray in the presence o… - 34-074 Feb 25, 2021 · Service Bulletin/Repair Instructions
The current chassis harness connector contains a wire that is no longer necessary with the latest electrical architecture. The presence of the wire could result in a false fault code. - 02-160 Feb 10, 2021 · Service Bulletin/Repair Instructions
Information Only – Windshield washer pumps have a high No Trouble Found rate. Washer pumps may fail to spray due to a clogged filter. - 20 PBF Dec 2, 2020 · Service Bulletin/Repair Instructions
Safety Recall: Interim Dealer Notification - Peterbilt has decided that a condition affecting vehicle stability may exist in certain Model 520 vehicles built from 9/26/2019 through 7/22/2020 with stability control and a spring brake modulator valve (SBM) o… - 13-055 Oct 1, 2020 · Service Bulletin/Repair Instructions
Fix as Fail: Peterbilt has introduced an improved mounting bracket for low mount air tanks for vehicles built between January 01, 2017 and July 06, 2020. Torsional vibration may stress the currently-installed brackets and cause them to fail near the bottom… - 20PBE Sep 16, 2020 · Service Bulletin/Repair Instructions
Safety Recall: Peterbilt has decided that a condition could exist in certain model 348, 365, 367, 389, 520, and 567 vehicles built between 11/19/2019 and 4/09/2020. Vehicles equipped with Watson & Chalin SL2065 lift axles may have lower rear pivot bolts th… - 14-027 Sep 25, 2020 · Service Bulletin/Repair Instructions
Information only: In 2020, Peterbilt and Kenworth began using the same M10, M12, M16, and M20 frame fasteners on all vehicles. Torque specifications for these fasteners are different from previous fasteners. - 20PBD Aug 8, 2020 · Service Bulletin/Repair Instructions
Safety Recall: Model 520 vehicles with Right-Hand Stand-Up (“RHSU”) configuration built between February 15, 2019 and December 20, 2019 may have incorrect steering assist cylinder bracket bolts installed, which prevents proper retention of these bolts.The… - 13-054 Jul 29, 2020 · Service Bulletin/Repair Instructions
Fix-As-Fail - Bendix New-Gen Lightweight Steer Axle Drum Brake Spider Cracking - 32-015 Jun 8, 2020 · Service Bulletin/Repair Instructions
Information Only: This bulletin provides dealers with a battery warranty quick reference guide to ensure the appropriate tests for battery warranty are performed in order to prevent battery warranty claims filed with incorrect or incomplete information. - 43-067 Jun 10, 2020 · Service Bulletin/Repair Instructions
Fix as Fail: For all conventional models, except 387/587, equipped with Side-of-Cab (“SOC”) exhaust and built from 03/6/2006 to 1/20/2020, the clamps that secure the SOC exhaust stacks may not be tightened properly. This may allow the exhaust stack to rota… - 34-087 Jun 10, 2020 · Service Bulletin/Repair Instructions
Non-Safety Campaign: Peterbilt has determined that certain RHSU model 520 trucks, built from 7/16/2018 to 3/20/2020, may have been equipped with a Main Cab Harness that enables the Door Alarm to sound when it should be disabled. Model 520 vehicles with thi… - 11-001 May 29, 2020 · Service Bulletin/Repair Instructions
Information only: Hendrickson Softek front axle maintenance intervals and requirements. - 20PBB Mar 24, 2020 · Service Bulletin/Repair Instructions
Safety Recall: Peterbilt has decided that certain Model 320 and 520 trucks built between 2/20/2015 and 7/16/2019 may have been built without a quick release valve. The absence of this valve could affect rear brake timing on certain vehicles equipped with a… - 19PBF Mar 3, 2020 · Service Bulletin/Repair Instructions
Safety Recall: Peterbilt Motors Company has decided a defect, which relates to motor vehicle safety, may exist in certain Model 520 vehicles with Right Hand Stand Up (RHSU) configuration built between June 15, 2018 and February 14, 2019. Vehicles may have … - 32-016 Mar 17, 2020 · Service Bulletin/Repair Instructions
Information Only: Proper jump-starting voltage will eliminate high voltage related issues and equipment damage. - 19PBF Jan 31, 2020 · Service Bulletin/Repair Instructions
Safety Related Campaign - Interim Notification: Peterbilt Motors Company has decided a defect, which relates to motor vehicle safety, may exist in certain Model 520 vehicles with Right Hand Stand Up (RHSU) configuration built between June 15, 2018 and Febr… - 03-071 Dec 18, 2019 · Service Bulletin/Repair Instructions
Information Only - Vehicles built with NAMUX software from 2013 to present may experience accuracy issues with the tachometer. The issue can be temporarily resolved using any one of the included procedures. - 19PBG Dec 20, 2019 · Service Bulletin/Repair Instructions
Safety Recall: Peterbilt Motors Company has determined that a defect, which relates to motor vehicle safety, may exist in certain model 348, 367, 389, 520 or 567 vehicles manufactured between November 22, 2019 and December 5, 2019. Output shafts may not ha… - 02-153 Nov 22, 2019 · Service Bulletin/Repair Instructions
Information only: Some model 320 and 520 vehicles built before 3/11/2019 may experience loss or loosening of doghouse insulation. Reference the procedure in the attachment section to properly remove and replace the insulation. - 01-075 Nov 6, 2019 · Service Bulletin/Repair Instructions
Information Only: This bulletin provides guidance for repairing an air-conditioning system after internal failure of the A/C compressor. - TIB43-062 Sep 27, 2019 · Service Bulletin/Repair Instructions
Information Only â“ This bulletin provides information about the California Air Resources Board (CARB) Periodic Smoke Inspection Program (PSIP) and Heavy Duty Vehicle Inspection Program (HDVIP). - 42-056 Aug 28, 2019 · Service Bulletin/Repair Instructions
Fix-As-Fail -“ Composite fittings used in the cooling system may crack, resulting in coolant leaks. Brass fittings are available to replace the composite fittings. - 42-058 Aug 23, 2019 · Service Bulletin/Repair Instructions
Fix-As-Fail: Two separate causes have been identified as root cause of intermittent low coolant indicator illumination. - 19PBC Jul 19, 2019 · Service Bulletin/Repair Instructions
Safety Recall: Vehicles fail to confirm with FMVSS/CMVSS No 108 Table 1-a requirements which requires 2 red stop lamps. Vehicles were equipped with additional amber stop lamps which may illuminate when the brake is applied, and may confuse other drivers. … - 34-066 Jun 10, 2019 · Service Bulletin/Repair Instructions
Information Only - Quick Reference Guide for Electric harness damage repairs. - 19PBB May 31, 2019 · Service Bulletin/Repair Instructions
Safety Recall: INTERIM NOTIFICATION - Peterbilt Motors Company has determined that a defect, which relates to motor vehicle safety, exists in certain model year 2017, 2018, 2019 and 2020 Model 520 vehicles manufactured between October 17, 2016 and March 04… - 34-077 Apr 8, 2019 · Service Bulletin/Repair Instructions
Information Only: Proper instructions for closure of power distribution box cover to prevent corrosion. - 34-074 Apr 4, 2019 · Service Bulletin/Repair Instructions
Non Safety Campaign: Vehicles were built with a 5 bolt supply wire for the air dryer pressure sensor that is no longer required with current architecture. If left in place, a fault code P1644 may be set.
Source: NHTSA manufacturer communications files.