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Service bulletins for the 2020 Peterbilt 579

A bulletin is a manufacturer's communication to its dealers, as NHTSA indexes it. The summary is NHTSA's. The document is the manufacturer's: read it at NHTSA. A bulletin is not a recall, and listing a model year does not mean every vehicle of it is concerned.

105 on file from NHTSA, as of 2026-10-19.

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Only bulletins with type: Service bulletin are shown. Show all

Bulletins, newest first
42-0702026-10-17. Service bulletin. UNKNOWN OR OTHER. Due to supplier constraints, an authorized aftermarket surge tank has been made available.
P0012026-09-29. Service bulletin. ENGINE. "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."
E3432026-09-23. Service bulletin. ENGINE. An exhaust manifold slip joint seal kit is now available for EPA 2017-2024 PACCAR MX-13 engines.
43-0882026-08-20. Service bulletin. ENGINE. 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.
E3112026-07-30. Service bulletin. ENGINE. 105 chassis have been removed from the chassis list and unflagged in PRWS due to expiration of applicable warranty coverage. Total chassis population is 732.
43-0882026-07-23. Service bulletin. ENGINE. 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 recently updated regulatory agency guidance.
41-0292026-07-22. Service bulletin. ENGINE. Incorrect air filters may be inadvertently installed in certain chassis equipped with under-hood Donaldson air filter housings.
E3112026-07-21. Service bulletin. ENGINE. The Condition, Chassis Affected, Service Action, Warranty, and Procedure sections have been updated to include the latest prognostics bulletin verbiage.
43-0882026-07-21. Service bulletin. ENGINE. "The software is not yet available. The bulletin will be updated when more information is available."
43-0882026-07-02. Service bulletin. ENGINE. "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 is being offered to customers in alignment withrecently updated regulatory agency guidance."
02-1772026-06-03. Service bulletin. ELECTRICAL SYSTEM. Troubleshooting procedures for 2.1m cab power windows are now available.
41-0242026-05-20. Service bulletin. ENGINE. Procedures have been updated to include additional truck models in the service intervals table.
42-0642026-05-06. Service bulletin. ENGINE. Fix-as-Fail On certain Kenworth T680 chassis equipped with PACCAR MX-13 engines, wiring to the Horton LCX230 crank-mounted fan drive may experience a short due to chafing or water ingress, affecting fan drive operation.
45-0702026-05-06. Service bulletin. ENGINE. The attached procedures document has been updated with more detail and explanations. This is not a stand-alone procedure. Cummins Quickserve troubleshooting will specify the use of these procedures while troubleshooting specific fault codes.
14-0342026-05-06. Service bulletin. UNKNOWN OR OTHER. Bogie Crossmember Torque Value Update - Procedure has been updated to correct torque values.
41-0242026-04-07. Service bulletin. ENGINE. Engine Air Filter Servicing UPDATE - Procedures are available to support the maintenance, service intervals, and intake system inspection process for all engine air intake system components.
45-0702026-02-05. Service bulletin. ENGINE. Procedure pictures updated for clarity. When troubleshooting Cummins X15 fault codes 555 or 556, follow this additional testing, inspection, and documentation procedure to help identify the root cause of dusted engines. This is not a stand-alone process but must be used alongside Cummins troubleshooting steps. Cummins Quickserve will reference this bulletin for fault codes 555 or 556.
T016 / 26-0402025-06-05. Service bulletin. POWER TRAIN. T016: Warranty section updated to include 0.5 hours for test drive. Recommended Repair T016C has been updated from 6.4 hours to 6.9 hours. SRT codes updated in PRWS Claim Coding Table: B25-17A for 6.9 hours created to replace all other codes. 26-040: Warranty section updated to include 0.5 hours for test drive. Recommended Repair 26040C has been updated from 6.4 hours to 6.9 hours. SRT codes updated in PRWS Claim Coding Table: B25-17A for 6.9 hours created to replace all other codes.
98-0302025-06-05. Service bulletin. ELECTRICAL SYSTEM. 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.
32-0252024-12-03. Service bulletin. ENGINE. 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.
46-0142024-10-05. Service bulletin. UNKNOWN OR OTHER. Information Only Storage guideline procedures are now available for both Medium Duty and Heavy-Duty Battery Electric Vehicles.
16-0442024-08-02. Service bulletin. SUSPENSION. 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.
36-1912024-06-04. Service bulletin. VISIBILITY/WIPER. Information Only Vehicles equipped with Digital Vision System (DVS) Mirror Mounted Cameras, that do not have optional left-hand or right-hand blind spotters, may set false Diagnostic Trouble Codes (DTC) 522490-9 or 522491-9. These DTCs can be ignored if corresponding blind spotter is not equipped. The next Digital Vision System Mirrors (DVS-M) software update will correct these false DTCs.
E2732023-12-02. Service bulletin. ENGINE AND ENGINE COOLING. Fix As Fail Updated: Two part numbers added: 1818119 DPF Delta Pressure Sensors for MX-13-2 EMY18 2200138 DPF Delta Pressure Sensors for MX-13 -2, EMY19 Per Environment and Climate Change Canada (ECCC) regulations and guidance (Canadian Environmental Protection Act, 1999 (CEPA)), a letter has been provided to owners of Canadian registered chassis that provides a list of emissions components that have been reported (to ECCC) as having a defect.
45-0662023-11-10. Service bulletin. ENGINE AND ENGINE COOLING. A testing procedure has been created for the coolant level sensor on model 520.

The summaries are NHTSA's. Each bulletin's page links NHTSA's copy of the manufacturer's document.