A method is provided for remanufacturing a transmission assembly including an output shaft having an input end positioned adjacent an input sun gear. The method includes machining a pocket into the input end of the output shaft. A first roller needle bearing is positioned inside the pocket. The input sun gear is then replaced with a modified sun gear having a protruding center support hub configured to extend into the pocket and cooperate with the first roller needle bearing, thereby supporting the output shaft to prevent tilting of the output shaft to reduce wear.