A system for lapping gear sets with a ring gear and a pinion gear. The system includes a lapping machine tool and a robot. The lapping machine tool has a first spindle and a second spindle. The second spindle is rotatable about an axis that is generally perpendicular to a rotational axis of the first spindle. The lapping machine tool has a loading zone for loading the first and second spindles. The robot has an end effector with a first end that is configured to hold one of the gear sets. The robot is configured to position the first end of the end effector into the loading zone and to load the first gear set to the lapping machine tool without removing the end effector from the loading zone such that the ring gear is loaded onto the first spindle and the pinion gear is loaded onto the second spindle.