A multi-terrain motorized wheelchair apparatus is disclosed that comprises a seating assembly for supporting a user in a seated position, a track assembly with the seating assembly being pivotable with respect to the track assembly. The track assembly includes a pair of track units positioned on opposite sides of the seating assembly. The apparatus comprises a seating orientation adjustment assembly configured to adjust an orientation of the seating assembly with respect to the track assembly. The apparatus includes at least one drive assembly mounted on the seating assembly and which has at least one drive shaft structure connected to the track units to drive the track units. The seating assembly is supported on the track units of the track assembly by the drive shaft structure.