This full billet rear clutch retaining hub is made from 4140 heat-treated, stress-relieved billet steel versus the OE cast piece. The factory cast retainer is known to fail in high torsional fatigue situations such as higher line pressure, commercial use and heavy duty towing and hauling. This new billet piece is the correction you've been looking for.
CA Residents: WARNING: Cancer and Reproductive Harm www.P65Warnings.ca.gov