apply piston kit 4th 5th 6th clutch high capacity 6l80 6l90 myc myd ly6Sonnax High Capacity 4 5 6 Clutch Apply Piston Kit for 6L80, 6L90 Designed for use with OE style, 36 tooth friction plates and original equipment steel plates, the Sonnax 4 5 6 clutch apply piston kit 104960 10K is engineered to resolve common failure points in GM 6L80 and 6L90 transmissions. Factory clutch assemblies often fail due to insufficient clutch count and limited apply surface area between the piston and clutch pack. Additionally, the OEM