Contact between the aluminum GM Powerglide ring gear and the Reverse clutch pack pressure plate causes damage to both components and generates metal debris that circulates throughout the transmission. The OE design with direct metal-to-metal contact is tolerable at original speeds, but is a far greater concern in racing transmissions at higher operational speeds. Sonnax ring gear anti-wear washer kit 28510-AW fits over the ring gear, preventing metal-to-metal contact between the ring gear and Reverse clutch pack pressure plate. The anti-wear washer will work with any ring gear that accepts stock-type reverse clutch plates.
Contact a Sonnax Parts Distributor.