An electromechanical strut is provided for moving a pivotal closure member between an open position and a closed position relative to a motor vehicle body. The electromechanical strut includes a drive mechanism having a motor-gearbox assembly that is operable to drive a rotatable power screw. The drive mechanism converts rotary motion of the power screw into linear motion of an extensible member to move the extensible member between a retracted position corresponding to the closed position of the closure member and an extended position corresponding to the open position of the closure member. The motor-gearbox assembly includes a gearbox unit equipped with a dual-stage planetary geartrain that is operably disposed between a motor output and the power screw. The dual-stage planetary geartrain includes a first stage gearset and a second stage gearset sharing a common ring gear.