24KWL/PBL
Service Bulletin/Repair Instructions
The verbiage in the Introduction section has been updated.
Vehicle report
2021 PETERBILT 520
Service bulletins
47 bulletinsTechnical service bulletins are instructions a manufacturer sent its dealers about a known fault. They are not recalls and the work is usually not free, but they are the clearest signal of a problem the manufacturer already knows about.
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.
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.
25KWD 25PBD
Service Campaign
Additional US chassis have been added, along with additional Canadian chassis under identical safety recall 26PACB.
CE030
Warranty Program/Extension
KW & PB 14 fuel injector part numbers (seven for MX-11 and seven for MX-13 engines) have been added to this warranty policy.
43-080
Service Bulletin/Repair Instructions
KW: A new recommended repair has been added to verify the software level and close the campaign in SIR.The repair procedure has been updated with additional note boxes for clear instructions. PB: The repair procedure has been updated with additional note boxes for clear instructions.
R2103
Service Bulletin/Repair Instructions
Updated the point of contact for sourcing the MX Engine Overlay Harness Kits. This retrofit should have been completed by 5/15/2022 per the Action section of the bulletin. However, trucks still open in SIR are still eligible for the repairs.
46-028
Service Campaign
Certain Peterbilt Model 520 BEV chassis with an Accelera Power Control and Accessory System (PCAS) were manufactured without a check valve in the power steering system.
E326
Emissions
EPA17-24 MX Fuel Injector Connector - This bulletin has been revised to include all EPA17-24 and CARB24 PACCAR MX engines.
01-090
Service Bulletin/Repair Instructions
Repair procedures and warranty information for model 520EV are now available. The cab heater coolant system on Peterbilt 579EV and 520EV models may not deaerate properly, causing pump malfunctions and inadequate cab heating. Update coolant deaeration return line parts and procedures are now available to release trapped air back to the reservoir.
46-019
Service Bulletin/Repair Instructions
Repair procedures and warranty information for model 520EV are now available. Certain Peterbilt 579EV and 520EV chassis have the First Responder Guide (FRG) label incorrectly showing the cut loop on the wrong side and are missing the Low Voltage Battery Disconnect Switch and Do Not Jump Start labels. These labels are now available for installation.
98-030
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 reducing risk of component damage. 4/29/2025: The Ethernet Multiplexed Architecture (EMUX) Service Tool Kit and individual kit components are now available to order. Dealers that have received their first kit may order an additional kit. The EMUX Service Tool Kit Part number has been updated to match OEM drawings (P74-1045-001). Individual kit component part numbers can be found in the Reference Bill of Materials sheet. The new EMUX Service Tool Kit improves cab & chassis electrical troubleshooting efficiency, while reducing risk of component damage. 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.
46-016
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 software update is available for 520EV and 579EV Battery Electric Vehicles. This software update corrects or improves certain functions. Campaign start date is 12/05/2024.
43-080 PB
Service Campaign
As of 03/25/2025, this campaign has resumed. Software updates are now available to complete this campaign.
E327
Emissions
Vehicles equipped with PACCAR MX engines with Engine Software Version NA202 or NA206 may display a dash STOP lamp incorrectly. PCI-2 software on these chassis must be reverted from NA202 to NA201 (Pack 2 injectors) or from NA206 to NA191 (Pack 1 injectors) to prevent incorrect STOP lamp display. 11014768 20250304 E327 20250227 E327 Emissions PETERBILT 520 2021 ENGINE Vehicles equipped with PACCAR MX engines with Engine Software Version NA202 or NA206 may display a dash STOP lamp incorrectly. PCI-2 software on these chassis must be reverted from NA202 to NA201 (Pack 2 injectors) or from NA206 to NA191 (Pack 1 injectors) to prevent incorrect STOP lamp display.
46-013
Service Campaign
Certain Peterbilt 579EV and 520EV Battery Electric Vehicles were built prior to the availability of certain labels and Low Voltage Distribution System (LVDS) Components. Affected chassis will be inspected and necessary components will be installed.
24PBL
Service Bulletin/Repair Instructions
Safety Recall Updated software and procedures are now available. Certain Vehicle Model Year 2021-2025 Peterbilt chassis configured for trailer towing require a software update for the Bendix EC80 ABS ECU. Software update procedures for certain Battery-Electric Vehicles (BEV) and EC80 ABS ECU part numbers are not yet available. This bulletin will be updated when software update procedures are available for these chassis. Safety Recall publish date: 1/10/25
46-011
Service Bulletin/Repair Instructions
Some 579EV and 520EV BEV trucks may have loose or improperly torqued ESS gland nuts. This may cause an intermittent warning light on the dash display.
32-025
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 starter replacements and associated warranty claims. Engine starting system warranty claims now require a completed Starter Checklist, a Battery Pack Midtronics Report, and a Cable Drop Midtronics Report. Claims filed without these documents may be denied.
7-700
Warranty Program/Extension
7/700 Service Agreement - Letter Only.
E290
Service Bulletin/Repair Instructions
FIX-AS-FAIL Updated to include EPA2024 compliant engines. Fuel Filters must be changed before first cleaning. EPA2021 injector cleaning is referenced in RMI for certain injector faults. Complete the procedures in E290. Discard any previous versions of E290 procedures – always use the most current document from the link in the bulletin.
46-014
Service Bulletin/Repair Instructions
Information Only Storage guideline procedures are now available for both Medium Duty and Heavy-Duty Battery Electric Vehicles.
16-044
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 results in either deflated airbags or makes them unable to inflate. Fix-as-fail start date is 07/30/2024.
46-003
Service Bulletin/Repair Instructions
A software fix for model 520EV that are not equipped with ESP (Stability Control) is now available. The currently available soft ware, part number:SCM_1p5_BC_R5p00_003, will address issues caused by software version R5.00_002 that affect Peterbilt Model 520EV. The software update will correct the following issues: 1.) Power gauge displays axle RPM instead of power draw, 2.) Air conditioning compressor is inoperative below 10 mph (16 kmh) and over 40 mph (65 kmh), 3.) Low air and low coolant audible alarms (buzzers) are inoperative below 10 mph (16 kmh), and 4.) (520EV Only) Does not charge without ignition in on position.
E306
Service Bulletin/Repair Instructions
Incorrect fuel filter drain and replacement procedures on EPA21 MX-11 and MX-13 engines can result in the following: .Debris and contaminants introduced into the high-pressure fuel system. .Denial of warranty claims for injector and/or fuel system faults. .Misfire, rough running, engine knock, and other associated faults and symptoms. Correct fuel filter procedures are outlined in attached service documentation.
R2304
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 to be updated with software released after February 2021.
E300
Service Bulletin/Repair Instructions
PACCAR will reimburse customers for the local purchase of in-tank fuel additive for EPA2021 compliant MX engines. This is a one-time reimbursement. Only customers who have received E290 injector cleaning qualify for this reimbursement. See bulletin for limits and purchase tracking requirements.
45-064
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 deliver secure software updates remotely. This will reduce downtime and save on maintenance costs for eligible vehicles.
13-060
Service Bulletin/Repair Instructions
The service information for Bendix Air Dryer maintenance is being updated to include new procedures.
01-085
Service Bulletin/Repair Instructions
Info Only â 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. A specific tool is available from the supplier that will allow a technician to bypass this design issue.
E294
Service Bulletin/Repair Instructions
Information Only - This bulletin is to provide information about the availability of a fuel filter set for Pre-Production or Validation level chassis. This fuel filter set is available directly from a PACCAR dealership parts department.
E286
Service Bulletin/Repair Instructions
Fix-As-Requested - âââEngine Model Year 2021B and later PACCAR MX-11 & MX-13 Fuel Injector Adjustment During First C Service
TIB 98-020
Service Bulletin/Repair Instructions
Information Only â New Level 1 required tools are available to support MY21B MX engines.
51-013
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 primary antenna may experience this degradation.
E282
Service Bulletin/Repair Instructions
Information Only: Due to differences between the PACCAR MX-11 or MX-13 2021A and 2021B engines, technicians must be able to identify which of these engines are in a chassis.
E280
Service Bulletin/Repair Instructions
Non-Safety Campaign: Certain DC tools were incorrectly calibrated. The resulting torque issue could affect the EPA21 MX-11 and MX-13 Oil Pan and/or the Exhaust Manifold.
21 PBK
Service Bulletin/Repair Instructions
âSafety Recall â 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-Up steering configurations. Vehicles will be inspected and, if necessary, a QR valve will be installed.
43-071
Service Bulletin/Repair Instructions
Fix-As-Fail â 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 operation with a failed DEF sensor by disabling the DEF sensor diagnostics.
21 PBG
Service Bulletin/Repair Instructions
âSafety Recall - Model year 2021 Cummins PX9 fuel hose assemblies may leak from the hoses between the fuel pump and the remote filter head. A fuel leak in the presence of an ignition source may increase the risk of a fire. A repair is now available.
21-PBD
Service Bulletin/Repair Instructions
Safety Recall â Cummins Fuel Rail Leak â 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 of an ignition source may increase the risk of fire.
15-029
Service Bulletin/Repair Instructions
Information Only - Power steering reservoir cap may separate during removal when it is pulled upward instead of twisted.
34-074
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
Service Bulletin/Repair Instructions
Information Only â Windshield washer pumps have a high No Trouble Found rate. Washer pumps may fail to spray due to a clogged filter.
13-055
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 of the frame rail.
34-087
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 this configuration should have the door alarm disabled when the passenger door is open and the vehicle is in drive mode.
43-067
Service Bulletin/Repair Instructions
Fix as Fail: For all conventional models, except 387/587, equipped with Side-of-Cab (âSOCâ) 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 rotate and contact the cab or sleeper.
32-015
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.
Reading this report
Complaint counts are reports filed with NHTSA, not failure rates. A common model collects more of them than a rare one that breaks more often.