A steerable hydraulic transaxle (15) comprises: a kingpin (26) relatively rotatably supported by a vehicle chassis (14); a housing (28) fixed to the kingpin (26); a single axle (35) disposed in the housing (28); a single wheel (36) fixed onto the single axle (15) out of the housing (28); and a hydraulic motor (10) disposed in the housing (28) so as to drive the single axle (15).
A hydraulic transaxle comprises a transaxle casing for supporting left and right axles, a pair of hydraulic motors (10) disposed in the transaxle casing so as to drive the respective left and right axles (15), hydraulic ports provided in the transaxle casing so as to fluidly connect the pair of hydraulic motors (10) in parallel to a common hydraulic pump (5), and a system for restricting or canceling differential rotation of the pair of hydraulic motors.