Vehicle report
Technical 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
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.
E326
EPA17-24 MX Fuel Injector Connector - This bulletin has been revised to include all EPA17-24 and CARB24 PACCAR MX engines.
98-030
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
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.
32-025
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
7/700 Service Agreement - Letter Only.
46-014
Information Only Storage guideline procedures are now available for both Medium Duty and Heavy-Duty Battery Electric Vehicles.
16-044
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.
R2304
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.
45-064
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
The service information for Bendix Air Dryer maintenance is being updated to include new procedures.
01-085
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.
51-013
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.
R2103
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.
21 PBK
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
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-PBD
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.
45-062
âFix-As-Fail â PX9 oil pan may leak due to improper hardware. Revised hardware will resolve the leak.
34-074
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
Information Only â Windshield washer pumps have a high No Trouble Found rate. Washer pumps may fail to spray due to a clogged filter.
20 PBF
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) or lift axle. The Stability Control Relay may have been plumbed incorrectly, which could cause a stability event that may actuate the lift axle brakes or modulate the park brake chambers, which could destabilize the vehicle. This bulletin will be updated as soon as an affected chassis list is defined and a repair procedure is developed.
13-055
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.
14-027
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.
20PBE
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 that are not long enough to sufficiently engage the locking feature of the corresponding nuts. In some cases, this condition may cause a loss of clamp load of the pivot joint (arm to axle). Extended use of the lift axle in this condition can result in foreign object debris on the roadway, increasing the risk of a crash and/or injury.
20PBD
Safety Recall: Model 520 vehicles with Right-Hand Stand-Up (âRHSUâ) 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 steering assist cylinder bracket attached to the right front spring bracket with these bolts may also be damaged. The bolts installed may not have the required thread lock and this could result in loose or missing hardware. This may cause the bracket to flex or break and cause damage to adjacent components or lock up steering. Resolution is to remove and reinstall the steering gear assist bracket bolts with thread locker.
13-054
Fix-As-Fail - Bendix New-Gen Lightweight Steer Axle Drum Brake Spider Cracking
34-087
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
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
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.
11-001
Information only: Hendrickson Softek front axle maintenance intervals and requirements.
20PBB
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 tri-drive or liftable tag axle and Dual Seated or Right Hand Stand-Up steering configurations. Resolutoin is to inspect for a quick release valve installed, and if there is not one, to install a quick release valve.
32-016
Information Only: Proper jump-starting voltage will eliminate high voltage related issues and equipment damage.
19PBF
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 an improperly supported steering gear assist bracket due to the incorrect spring bracket installed. The spring bracket may be missing 3 drilled and tapped holes which will provide additional support for the steering gear assist bracket. An improperly supported steering gear assist cylinder bracket may break and cause damage to surrounding components and/or lock up the steering, increasing the risk of a crash. Resolution is to inspect and verify the steering assist bracket is installed with 5 required bolts. If 5 bolts are not installed, a new bracket will be installed.
19PBG
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 have been correctly heat-treated and could break near the pinion nut. Resolution is to inspect the driveshaft to verify the julian date, and if witin th esupect date rate,, replace the output shaft.
03-071
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.
02-153
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
Information Only: This bulletin provides guidance for repairing an air-conditioning system after internal failure of the A/C compressor.
TIB43-062
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
Fix-As-Fail -ÃÂ Composite fittings used in the cooling system may crack, resulting in coolant leaks. Brass fittings are available to replace the composite fittings.
42-058
Fix-As-Fail: Two separate causes have been identified as root cause of intermittent low coolant indicator illumination.
19PBC
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. Resolution is to remove the amber stop lamps and associated wiring.
34-066
Information Only - Quick Reference Guide for Electric harness damage repairs.
19PBB
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, 2019 with left hand or right hand single steer Power Distribution Center (PDC) harnesses. The power wire to the PDC may be inadequate and unable to accommodate the current draw. This can cause the wire to overheat and potentially melt the cab power harness connector. This could cause a loss of power to the cab and engine, which may result in the engine shutting down. A sudden loss of engine power could increase the risk of a crash.
34-077
Information Only: Proper instructions for closure of power distribution box cover to prevent corrosion.
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.