As part of the high-performance-seal kit used in every Lentech tranny, Teflon sealing rings are used in place of the factory's cast metal rings on the pump stator. The two pointed out with arrows are for the Reverse clutch, and two more are not yet installed at the top for the forward clutch. The Teflon rings prevent grooving or scoring of the clutch drums under higher line pressure. The large metallic ring on the back face of the pump is the intermediate band piston. An automatic lives or dies by its hydraulics, which are responsible for converter and shift operation, overall lubrication, and cooling. Lentech always changes the front bushing on the oil pump as well as various other bushings throughout the transmission whose clearances are essential in maintaining proper fluid pressures. A restrictor ball and spring are removed from the pump stator to increase fluid volume.