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Service bulletins for the 2021 Peterbilt 365

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.

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

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Bulletins, newest first
E3162024-09-10. Service bulletin. ENGINE. Bulletin updated to include oil pan drain plug in parts list and incorporated QR code to direct dealers to informational resources for new Programmable Torque Tool.
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.
E3162024-06-04. Service campaign. ENGINE. Campaign Certain PACCAR MX-13 engines contain bolts for the main bearing caps which may fail under certain conditions.
24PBE2024-04-03. Service bulletin. POWER TRAIN; ELECTRICAL SYSTEM. INTERIM Safety Recall Parts are not currently available for this safety recall. This bulletin will be updated once repair parts are available. The right-hand shift stalk may have an improper wire harness terminal crimp within the wire harness connector. Loss of communication between the right-hand shift stalk and the transmission may result in the vehicle becoming disabled after it comes to a stop thereby increasing the risk of crash or injury. A transmission fault will appear on the dash display if communication is lost.
R21052024-03-04. Service bulletin. ELECTRICAL SYSTEM; STEERING:COLUMN. Peterbilt has determined that certain model year 2021, pre-production chassis are eligible to have specific parts updated to production level.
E3062023-11-10. Service bulletin. FUEL SYSTEM, DIESEL. 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.
23-0052022-11-04. Service bulletin. POWER TRAIN; VEHICLE SPEED CONTROL. Clutch pedal linkage lubrication service interval information is missing from the Service manual for Model 365, 367, and 389 chassis.
45-0642022-11-02. Service bulletin. ENGINE AND ENGINE COOLING. 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.
13-0602022-09-06. Service bulletin. SERVICE BRAKES. The service information for Bendix Air Dryer maintenance is being updated to include new procedures.
56-0052022-08-30. Service bulletin. ENGINE AND ENGINE COOLING. During PTO mode, the engine will not ramp up to the set RPM speed.
02-1692022-07-01. Service bulletin. ELECTRICAL SYSTEM; STRUCTURE. Info Only - Chassis equipped with a flush mounted battery box between the frame rails, and containing 3 batteries, may experience battery movement on the side where the single battery resides. This bulletin contains a procedure to fabricate a bracket to hold this battery in place.
E2862022-04-05. Service bulletin. FUEL SYSTEM, GASOLINE:FUEL INJECTION SYSTEM:INJECTORS; ENGINE AND ENGINE COOLING; EQUIPMENT. Fix-As-Requested - Engine Model Year 2021B and later PACCAR MX-11 & MX-13 Fuel Injector Adjustment During First C Service
TIB 98-0202022-04-05. Service bulletin. EQUIPMENT. Information Only – New Level 1 required tools are available to support MY21B MX engines.
13-0572022-04-05. Service bulletin. EQUIPMENT; SERVICE BRAKES, AIR; EQUIPMENT ADAPTIVE/MOBILITY; SERVICE BRAKES, HYDRAULIC. Fix-As-Fail – A hill start assist (HSA) valve plumbing revision eliminates ice buildup in the HSA valve exhaust in cold weather.
51-0132022-03-04. Service bulletin. EQUIPMENT. 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.
34-0902022-03-04. Service bulletin. EQUIPMENT; EXTERIOR LIGHTING; ELECTRICAL SYSTEM. A frame mounted left-hand marker light bracket interferes with the rear fuel tank fill location. A redesigned bracket can be purchased that relocates the marker bracket to the front fuel tank bracket to eliminate interference.
E2802022-01-06. Service bulletin. ENGINE AND ENGINE COOLING. 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.
E2822022-01-06. Service bulletin. ENGINE AND ENGINE COOLING. 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.
43-0712021-10-05. Service bulletin. FUEL SYSTEM, DIESEL. 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 operation with a failed DEF sensor by disabling the DEF sensor diagnostics.
02-1682021-10-05. Service bulletin. STRUCTURE. Information Only - Rear axle Quarter Fenders with less than two inches of clearance between the top of the quarter fender and the bottom of the trailer/equipment are susceptible to damage. The lack of clearance could result in cracked/broken quarter fenders or complete separation if undetected or un-remedied.
21-PBD2021-07-06. Service bulletin. FUEL SYSTEM, GASOLINE. 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 of an ignition source may increase the risk of fire.
15-0292021-06-02. Service bulletin. STEERING. Information Only - Power steering reservoir cap may separate during removal when it is pulled upward instead of twisted.
02-1602021-03-10. Service bulletin. VISIBILITY; EQUIPMENT; EQUIPMENT ADAPTIVE/MOBILITY; VISIBILITY:WINDSHIELD WIPER/WASHER. Information Only – Windshield washer pumps have a high No Trouble Found rate. Washer pumps may fail to spray due to a clogged filter.
13-0552020-11-05. Service bulletin. EQUIPMENT ADAPTIVE/MOBILITY; EQUIPMENT; SERVICE BRAKES, AIR. 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.
02-1582020-09-03. Service bulletin. EQUIPMENT; STRUCTURE; EQUIPMENT ADAPTIVE/MOBILITY; ELECTRICAL SYSTEM:12V/24V/48V BATTERY. Fix as Fail: Peterbilt has determined that certain model 348, 365, 367, 382, 384, 386, 388, 389, 567, 579, and 587 trucks, built between 4/13/2010 and 3/16/2020 and equipped with a flush mounted battery box, utilized rubber washers that could rub through and cause the aluminum box mounting tabs to rub directly on the steel frame brackets. This could result in cracked battery box mounting angles. Resolution is to add the reinforcement bracket(s) to affected vehicles.

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