5R110W, 8-Stud

Performance Converter Kit
Part No. FD-RK-21

View Instructions

When Ford 6.4 liter diesel engines are modified for racing or performance street use, OE clutch plates slip and fail to hold. Upgrading to an aftermarket multi-plate converter is the only solution.

Sonnax heavy duty, damperless multi-plate performance converter kit FD-RK-21 is available for Ford 5R110W, 8-stud converters. The Sonnax kit pairs the salvaged OE fluid coupling parts (impeller, stator and turbine) with new heavy duty front cover, clutch plates, piston and turbine hub to increase overall converter capacity. Clear instructions, minimal setup and easy assembly make these foolproof upgrades. All-new kit components eliminate the rework and limitations associated with salvaged parts.

  • Forged chromoly damperless piston features heat-treated splines and resists bending under extreme lockup pressure
  • Spring end caps limit how far springs compress under load to prevent breakage.
  • Increased oil flow improves cooling and lubrication of clutch plates
  • Three high-thermal, non-segmented and high-torque capacity friction elements deliver solid holding power
  • Turbine Hub
  • Turbine Hub Rivets (10)
  • Energizer Ring
  • Seal PTFE
  • Thrust Bearing
  • Damperless Piston
  • Clutch Plate with External Splines
  • Clutch Plate with Internal Splines
  • Front Cover
  • Transmission Unit: 5R110W
  • Unit Size: 12.5"
  • Core: Ford 5R110W, 8-Stud
  • Dampered: No
  • Lockup: Multi-Plate
  • Clutch Material: HTE
  • Turbine Hub Input Spline Count: 31

Where to Buy

  • Existing Customers: Contact your sales representative.
  • New Customers: Fill out the form and a sales representative will contact you.
  • 5R110W, 8-Stud Performance Converter Kit FD-RK-21

Sonnax Performance Converter Kits

Engineered to Deliver Builds that Last

Designed from the ground up to outperform OE and other aftermarket components, Sonnax has you covered with a full line of performance converter kits for gas and diesel vehicles. Offering the widest variety of options in the aftermarket, these innovative kits deliver customized performance and value.

  • Small/Large Diameter
  • Single-Plate/Multi-Plate/Non-Lockup
  • Dampered/Damperless


Choose the right kit for your rebuild!