A surgical system that includes a surgical end effector that has a first jaw and a second jaw, wherein one of the first and second jaws is movable between open and closed positions. A firing member is axially movable between a starting position and an ending position and is configured to slidably engage each of the first and second jaws. A firing drive member interfaces with a rotary output member, such that rotation of the rotary output member about a first rotary output axis imparts a firing motion to the firing member.