Extreme Duty Forward Clutch Hub Kit

The Sonnax 34322-02K is an extreme duty forward clutch hub kit designed for demanding applications. Constructed from forged 4140 steel, it features nitrited and case-hardened splines that prevent spline wear, even under extreme power and off-road conditions. This kit includes a bearing that is positioned between the hub and the direct clutch housing, effectively shifting the support of the forward clutch hub from the main shaft to the direct housing and sun gear shaft. Compared to OE or other replacement forward clutch hubs, the Sonnax 34322-02K offers an additional .025” thickness. This design helps to reduce endplay and provides further adjustment options. Installation typically requires no machining. The kit's design also allows for easy modification to add a second bearing. This kit is compatible with TH400, TH425, 4L80-E, and 4L85-E transmissions. However, it is not compatible with 1964-1966 TH400 main shafts that have a spline major diameter of approximately .980”. For use in these early units, a 1967-later main shaft is required. The Sonnax 34322-02K comes with a 6-month warranty.