Valvebody need to be changed with new one.Or with sonax full upgrades one.I changed it.No it is changing very good , but i rebuild all the transmission with this.Without touching the converter.All rebuild i have done is with OEM parts.About 4000$.I rebuild it by myself.With amsoil , two sensors and all transmission cables are changed with new OEM.Every !Removed! thing :). But still when i release the gas pedal and then press it it slams a little especialy on hot engine and tranny.I think somethink in converter is bad.