A surgical stapling instrument having an elongate shaft assembly, an articulation joint, and an end effector pivotally coupled to the elongate shaft assembly about the articulation joint is disclosed. The end effector comprises a first jaw and a second jaw pivotally coupled to the first jaw. A replaceable staple cartridge assembly comprises a cartridge body having a deck with a first tissue-facing surface comprising a plurality of staple cavities defined therein and a second tissue-facing surface stepped relative to the first tissue-facing surface. The replaceable staple cartridge further comprises a sled with a cutting surface. The end effector further comprises a drive screw extending longitudinally therewithin and a bearing, wherein a distal end of the drive screw is received by the bearing.