Tracsport 2000E rear gearbox housing cast in L169TF. The rear prop shaft bush cannot move forward because of the step in the bore prevents this from happening. The outside diameter of the seal location has been increased by two mm, to help prevent cracks to this area. The location slot for the lay shaft spindle is CNC machined in for accuracy, the width of which is narrower than standard to prevent radial movement of the lay shaft.