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Thoroughbred Heavy Duty Head Stud Kit - 98.5-21 Cummins

Thoroughbred Sku #: TDPFHSC9821
Manufacturer Sku #: FHSC9821

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Product Details

Product Name:Thoroughbred Heavy Duty Head Stud Kit - 1998.5-2021 Dodge Cummins
Manufacturer: Thoroughbred Diesel
Manufacturer Part #: FHSC9821
Thoroughbred Diesel Part #: TDPFHSC9821
Fitment Notes: 1998.5-2021 Dodge Cummins

When you invest in 5.9L/6.7L Cummins, you’re planning to keep it on the road for the long haul. At some point in the life of that engine,  the factory head screws will need to be upgraded to head studs. Thoroughbred Diesel makes this easy with their premium Head Stud Kit for your 1998.5-2021 Dodge 2500/3500 as it was specifically designed to strengthen up your truck's entire assembly without compromise. Thoroughbred Diesel’s head studs were built much stronger than the OE  head screws and will not stretch like their factory counterparts. This will prevent your truck from popping head gaskets during high-pressure situations

Premium Construction & Installation Info

Thoroughbred Diesel’s Head Stud Kit for your Dodge 5.9L/6.7L Cummins was engineered to ensure maximum durability in everyday driving situations as well as max towing. Rated at a Tensile Strength of over 220,000 PSI, these head studs were designed for stock to moderately built 5.9L and 6.7L Cummins Engines. Rest assured, your truck will be ready for just about everything you throw at it. When it comes to installation, these head studs were designed to directly replace your factory components to make for a simple and straightforward process you can complete at home.
Vehicle Fitment: 1998.5-2021 Dodge Ram 5.9L/6.7L Cummins

Thoroughbred Heavy Duty Head Stud Kit Features:

  • Manufactured by an ISO/TS 16949 certified facility.
  • 8740 Alloy Steel material commonly found in tool, engine and even aerospace applications, where overall toughness and wear resistance are key factors.
  • Rolled threads for strength and dimensional accuracy.
  • Tensile strength of over 220,000 PSI for Heavy Duty Series Kits.
  • Black Oxide Finish.
  • Chromoly steel 12 point nuts.


  • In what state are these head studs manufactured or are they made in China? Also, will these studs require the valve cover to be milled out to fit once installed or will there be no modification to the valve cover needed?

    TAYLOR M. | 1/9/2024

    Florida, It will be necessary to machine the lower rocker arm cover at the No. 24 bolt hole location

    in the torque sequence to facilitate installation of the lower rocker arm cover

  • Are these (Thoroughbred Diesel Brand) studs made to do one at a time , or do you have to remove the head to install them.

    Keith Lucking | 1/31/2023

    No head studs are made to be 1 at a time studs. We recommend removing the head to install.

  • I have 07 5.9 I will be running a s472/s488 compound set up with 200 over injectors will these hold for my setup

    Isaiah | 12/31/2022

    60 psi boost rating

  • What's the maximum hp rating for these studs?

    Michael Hostutler | 12/21/2022

    60 PSI rating.

  • Who makes these ? Are they American made?

    Alan | 12/8/2022

    Private manufacturer, yes.