A direct replacement impeller hub for the torque converter of an automatic transmission and a method of repairing an impeller assembly utilizing the replacement impeller hub to provide increased service longevity. In the present impeller hub the geometric roundness characteristic of the impeller hub is controlled to an exacting tolerance during the manufacturing process in accordance with American National Standards Institute (ANSI) definitions to provide a close tolerance fit within a mating bearing sleeve. The present impeller hub is also finish ground in accordance with ANSI definitions to reduce surface friction and to provide an optimal sealing surface for engagement with a radial seal, which is disposed about the impeller hub sealing it to prevent contaminants from entering the hydraulic pump of the transmission. The present impeller hub also includes additional structural features such as fillet radii machined on selected features to facilitate assembly of the torque converter.