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Service bulletins for the 2020 Kenworth T680

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.

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

By type

By component

By topic

Bulletins, newest first
26-0372021-01-06. Service bulletin. ELECTRICAL SYSTEM:SOFTWARE; POWER TRAIN; EQUIPMENT ADAPTIVE/MOBILITY. Fix-As-Fail - Prior versions of Eaton Endurant transmission software may be prone to setting Linear Clutch Actuator (LCA) fault codes leading to possible LCA hardware replacement.
32-0142020-11-05. Service bulletin. ELECTRICAL SYSTEM. Fix-As-Fail – The Battery Management System (BMS) may report the incorrect battery condition. Additional diagnostics are available to correctly determine and repair the root cause of the issue.
14-0272020-10-06. Service bulletin. STRUCTURE; EQUIPMENT. 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.
37-0012020-09-03. Service bulletin. EQUIPMENT; ELECTRICAL SYSTEM; ENGINE AND ENGINE COOLING. Fix-As-Fail – The Master Switch Module (MSM) may lose dash switch memory and functionality when the battery disconnect switch is cycled. An improved MSM is available to resolve the issue.
44-0332020-08-05. Service bulletin. FUEL SYSTEM, DIESEL. Non-Safety Campaign – The end cap welds on certain fuel tanks may not meet internal quality standards due to improper weld equipment settings. The fuel tanks will be replaced.
32-0152020-07-03. Service bulletin. ELECTRICAL SYSTEM. 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.
32-0162020-04-03. Service bulletin. EQUIPMENT. Information Only: Proper jump-starting voltage will eliminate high voltage related issues and equipment damage.
02-1572020-03-04. Service bulletin. VISIBILITY. Fix-As-Fail: The seal on T680, T880, and W990 windshields may be delaminated. Replace the windshield and encapsulated seal to resolve the issue.
32-0132020-02-05. Service bulletin. ELECTRICAL SYSTEM. Information Only: The AutoStart System Test does not recognize the hood opening and closing when running the test on a model 579 or 567 chassis equipped with a VECU software version 9.8 and 9.9. The issue will be fixed on a future VECU software update. This bulletin will be updated when the resolution is available.
36-0052020-02-05. Service bulletin. VEHICLE SPEED CONTROL; SERVICE BRAKES. Information Only - Driver Performance Assistance (DPA) Coasting and Braking Scores Not Incrementing, Stays at 50%. The average score will never change nor create driver assistance popups based upon driver’s actions. A future software update will resolve the issue. This bulletin will be updated when the software update becomes available.
03-0712020-01-04. Service bulletin. ELECTRICAL SYSTEM:SOFTWARE. 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.
22-0162020-01-04. Service bulletin. EQUIPMENT ADAPTIVE/MOBILITY; WHEELS; POWER TRAIN; EQUIPMENT. This bulletin has been obsoleted and replaced by Safety Recall 19KWE.
01-0752019-12-04. Service bulletin. ENGINE AND ENGINE COOLING. Information Only: This bulletin provides guidance for repairing an air-conditioning system after internal failure of the A/C compressor.
E2402019-12-04. Service bulletin. VEHICLE SPEED CONTROL. Fix As Fail-Shudder sensation near the governed vehicle speed when using cruise control due to excessive control messaging from VECU. A VECU software update is available to correct the condition.
TIB43-0622019-10-04. Service bulletin. EQUIPMENT; ENGINE AND ENGINE COOLING:EXHAUST SYSTEM. Information Only – This bulletin provides information about the California Air Resources Board (CARB) Periodic Smoke Inspection Program (PSIP) and Heavy Duty Vehicle Inspection Program (HDVIP).
42-0582019-09-05. Service bulletin. ENGINE AND ENGINE COOLING. Fix-As-Fail: Two separate causes have been identified as root cause of intermittent low coolant indicator illumination.
59-0022019-06-11. Service bulletin. LATCHES/LOCKS/LINKAGES; TRAILER HITCHES:FIFTH WHEEL ASSEMBLY; EQUIPMENT ADAPTIVE/MOBILITY. Non Safety Campaign: Holland Series FW17 fifth wheel handles may remain in an unlocked position when coupling to a parked trailer.
34-0772019-05-13. Service bulletin. EQUIPMENT:OTHER:OWNERS/SERVICE/OTHER MANUAL; EQUIPMENT:ELECTRICAL. Information Only: Proper instructions for closure of power distribution box cover to prevent corrosion.

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