2020 Kenworth T680 TSBs
67 Technical Service Bulletins across 13 categories
Categories
Engine
20 bulletinsAn exhaust manifold slip joint seal kit is now available for EPA 2017-2024 PACCAR MX-13 engines.
This optional software update is now available for chassis equipped with EMY 2021B-2023 PACCAR MX-11 and MX-13 engines.
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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.
"An optional software update will be available on 07/06/2026 for chassis equipped with EMY 2021B-2023PACCAR MX-11 and MX-13 engines.
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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."
Fix-as-Fail On certain Kenworth T680 chassis equipped with PACCAR MX-13 engines, wiring to the Horton LCX230...
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crank-mounted fan drive may experience a short due to chafing or water ingress, affecting fan drive operation.
KW & PB DEF Quality Sensor part number Q21-6127-001 for Cummins X15 engines has been added to this warranty policy.
EPA17-24 MX Fuel Injector Connector - This bulletin has been revised to include all EPA17-24 and CARB24 PACCAR MX...
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engines.
Engine Air Filter Servicing UPDATE - Procedures are available to support the maintenance, service intervals, and intake...
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system inspection process for all engine air intake system components.
EPA17-24 MX-13 Fuel Injector Connector - This bulletin has been revised to include EPA24 PACCAR MX-13 engines.
Procedure pictures updated for clarity.
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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.
SAFETY RECALL Additional chassis have been included.
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The chassis list has been updated. Certain T370 / T440 / T470 / T480 / T660 / T680 / T800 / T880 / W900 / C500 chassis may be equipped with air tank reservoirs that have less than twelve times the combined volume of all service brake chambers which fail to conform to Federal Motor Vehicle Safety Standard (FMVSS) No.121, Air Brake Systems.
Campaign Certain PACCAR MX-13 engines contain bolts for the main bearing caps which may fail under certain conditions.
Certain chassis with Engine Model Year 2016-2021 PACCAR MX-11/MX-13, or EPA13 and EPA21 Cummins ISX12/ISX15/X15 engines...
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that had a previously failed DEF sensor and with DEF sensor software disabled due to industry DEF sensor shortages will now be able to receive a replacement DEF sensor, DEF tank heater coolant control valve, and re-enabled DEF diagnostic software. Please note that chassis equipped with PACCAR PX engines will be eligible for this repair at a future date when software is available.
Certain Model Year 2021-2024 chassis with PACCAR MX engines and optional fuel filter restriction virtual gauge may...
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display incorrect restriction levels. The virtual gauge will be temporarily disabled until a revised sensor strategy is developed.
This campaign is the final opportunity to replace the oil filter screw cap to reduce occurrences of broken bypass valve tabs.
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Broken oil valve tabs can cause oil flow obstruction to critical engine parts, resulting in serious engine damage. Customers that do not receive this repair may be responsible for progressive engine damage caused by broken oil bypass valve tabs.
Info Only - PACCAR is introducing Over-the-Air (OTA) software updates for engine MY17 and newer chassis equipped with...
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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.
Kenworth is providing guidance for PACCAR MX Engine Composite Oil Pan leak troubleshooting to avoid over-repairs and to...
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provide warrantable repair guidance. Oil leaks, if not repaired, can lead to severe engine damage.
Retrofit - The emissions exemption will be expiring on 5/15/2022 for certain pre-production vehicles equipped with...
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PACCAR MX-11 and MX-13 EPA 2021 Emissions engines. Production-level components are now available to make these vehicles compliant.
Non-Safety Campaign Vehicles with a Cummins X15 engine and Horton fan drive may set Diagnostic Trouble Code (DTC) 6637...
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and/or 3838 due to fan speed that results in the fan remaining activated until the power is cycled. A new controller will resolve the issue.
T680 predictive cruise control(PCC) incompatibility with cummins engine.
Non-Safety Campaign - Vehicles included in Model Year 2021 Pre-Production Engine program have an Emissions Exemption label that must be replaced.
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The current Emissions Exemption label will expire on 12/31/2020 and requires a new label to extend the exempt
Software & Calibration
12 bulletinsThis bulletin, the troubleshooting procedure, and the BMS Troubleshooting Checklist have been updated to show that the...
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Autometer tool test results can be used in place of the Midtronics tool test results for fulfilling service and warranty requirements.
The Condition, Chassis Affected, Service Action, Warranty, and Procedure sections have been updated to include the...
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latest prognostics bulletin verbiage.
"The software is not yet available.
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The bulletin will be updated when more information is available."
Updated Eaton's TAIB0885EN Bulletin link.
The PACCAR Powertrain Prognostics Webcast video link has been removed.
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It will be included with updated information at a later date.
Kenworth - The Warranty section has been updated to include Peterbilt-specific SRT codes for cross-division repair...
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filing.
Procedures have been updated to include additional truck models in the service intervals table.
The attached procedures document has been updated with more detail and explanations.
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This is not a stand-alone procedure. Cummins Quickserve troubleshooting will specify the use of these procedures while troubleshooting specific fault codes.
Bogie Crossmember Torque Value Update - Procedure has been updated to correct torque values.
Certain vehicle model years 2020-2025 K270, K370, T270, T280, T370, T380, T480, T680, T880, W900 chassis have updated...
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Greenhouse Gas (GHG) labels available for installation.
Condition, Chassis Affected, and Warranty sections updated with the following verbiage E311 must be flagged and open in...
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Service Information Record (SIR) at the time of RO open date to qualify. Also, Through Standard Warranty or any applicable active Extended Warranty verbiage was removed from Warranty section.
Information Only - Vehicles built with NAMUX software from 2013 to present may experience accuracy issues with the tachometer.
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The issue can be temporarily resolved using any one of the included procedures.
Electrical
11 bulletinsThe procedure has been updated to include additional steps for verifying the software level on the vehicle electronic...
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control unit (VECU2) and digital display (DD). Steps have also been added to the PACCAR Common Rail Injection 2 (PCI2) software verification.
Fix-As-Fail Due to undersupply issues, only a limited supply of Diesel Exhaust Fluid (DEF) sensors are available.
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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.
Information Only C hassis equipped with MY2021 B EPA emission s standards will be shipped through atleast ...
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the end of the 2021 calendar year without particulate matter (PM) sensors installed .
Non-Safety Campaign Chassis with the City Horn option may generate unexpected alerts.
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A VECU software update is available to resolve the issue.
Non-Safety Campaign The batteries may drain quickly due to the VECU not going to sleep.
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Updated VECU software is available to resolve the issue.
Fix-As-Fail The Battery Management System (BMS) may report the incorrect battery condition.
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Additional diagnostics are available to correctly determine and repair the root cause of the issue.
Fix-As-Fail The Master Switch Module (MSM) may lose dash switch memory and functionality when the battery disconnect switch is cycled.
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An improved MSM is available to resolve the issue.
Information Only: This bulletin provides dealers with a battery warranty quick reference guide to ensure the...
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appropriate tests for battery warranty are performed in order to prevent battery warranty claims filed with incorrect or incomplete information.
Information Only: Proper jump-starting voltage will eliminate high voltage related issues and equipment damage.
Information Only: The AutoStart System Test does not recognize the hood opening and closing when running the test on a...
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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.
Fix As Fail-Shudder sensation near the governed vehicle speed when using cruise control due to excessive control messaging from VECU.
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A VECU software update is available to correct the condition.
Body & Paint
6 bulletinsIncorrect air filters may be inadvertently installed in certain chassis equipped with under-hood Donaldson air filter...
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housings.
Troubleshooting procedures for 2.1m cab power windows are now available.
Information Only - Rear axle Quarter Fenders with less than two inches of clearance between the top of the quarter...
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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.
Information Only Windshield washer pumps have a high No Trouble Found rate.
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Washer pumps may fail to spray due to a clogged filter.
Fix-As-Fail: The seal on T680, T880, and W990 windshields may be delaminated.
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Replace the windshield and encapsulated seal to resolve the issue.
Information Only: Proper instructions for closure of power distribution box cover to prevent corrosion.
Other
4 bulletins"Kenworth: Dealers should check the chassis list and SIR weekly for VIN changes.
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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."
Certain T680 NextGen air filter elements that may have been damaged due to excessive vibration were replaced without...
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inspecting the air intake system for dust intrusion. Those vehicles must be inspected to assess possible progressive damage."
Information only: In 2020, Peterbilt and Kenworth began using the same M10, M12, M16, and M20 frame fasteners on all vehicles.
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Torque specifications for these fasteners are different from previous fasteners.
Fix-As-Fail: Two separate causes have been identified as root cause of intermittent low coolant indicator illumination.
Fuel System
3 bulletinsReplacement fuel bezels are available for T680 Next Gen fairings.
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New bezels have updated attachments to prevent the bezel from becoming loose.
Due to major data carriers phasing out 3G networks, chassis currently utilizing first generation Peoplenet Mobile...
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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
Non-Safety Campaign The end cap welds on certain fuel tanks may not meet internal quality standards due to improper weld equipment settings.
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The fuel tanks will be replaced.
Transmission
3 bulletinsNon-Safety Campaign: Drivers of vehicles equipped with PACCAR TX-12 transmissions may experience harsh shifts and gear grinding noise.
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Premature Main Drive Gear damage may occur due to clutch housing and main case countershaft bearing bore wear.
Non-Safety Campaign: Eaton Endurant transmissions may experience premature Main Drive Gear damage due to clutch housing...
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and main case countershaft bearing bore wear. A Clutch Housing Front Cover Kit will be installed to address the issue.
Fix-As-Fail - Prior versions of Eaton Endurant transmission software may be prone to setting Linear Clutch Actuator...
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(LCA) fault codes leading to possible LCA hardware replacement.
Brakes
2 bulletinsCertain C500/T440/T470/T660/T680/T800/T880/W900 chassis may have air tank reservoirs that do not meet air volume...
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requirements per FMVSS/CMVSS 121 Air Brake Systems. This bulletin will be updated when repair parts and procedures are available.
Information Only - Driver Performance Assistance (DPA) Coasting and Braking Scores Not Incrementing, Stays at 50%.
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The average score will never change nor create driver assistance popups based upon drivers actions. A future software update will resolve the issue. This bulletin will be updated when the software update becomes available.
Pre-Delivery & Maintenance
2 bulletinsThis bulletin has been obsoleted and replaced by Safety Recall 19KWE.
Information Only This bulletin provides information about the California Air Resources Board (CARB) Periodic Smoke...
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Inspection Program (PSIP) and Heavy Duty Vehicle Inspection Program (HDVIP).
Suspension
1 bulletinCertain T680 Next Gen Cummins X15 have fan hub bracket hardware that is under torqued and could become loose and/or fail.
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Procedures are available to replace and properly torque the hardware.
Steering
1 bulletinSafety Recall Interim Notification - The Dana D-Series front axle steer arm fasteners that attach the steer arm to the...
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steering knuckle may fail, increasing the risk of a crash or injury. Repair information will be added when a repair procedure and parts are available.
HVAC & Climate
1 bulletinInformation Only: This bulletin provides guidance for repairing an air-conditioning system after internal failure of the...
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A/C compressor.
Tires & Wheels
1 bulletinNon Safety Campaign: Holland Series FW17 fifth wheel handles may remain in an unlocked position when coupling to a...
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parked trailer.