The Borg Warner 310mm, Chrysler A618 piston damper cores are becoming scarce. After several rebuilds, the material supporting the friction material becomes weak, and deflection could result in failure. The Sonnax fully machined piston allows for a stronger and more durable replacement. The hardened bore reduces galling of the seal bore. The piston plate BW-DA-3P adapts to the OE damper assembly using BW-RV-2 rivets.