An electric actuator for an automatic transmission includes an adapter to transmit rotary motion between the adapter and the transmission. An electric motor has an output shaft operably connected the adapter by a gear set which includes a ring gear. A release mechanism includes a solenoid which selectively moves a lock member. In a first position, the lock member engages the ring gear to lock the ring gear so that the adapter is rotated by rotary motion of the output shaft and the adapter rotates to a predetermined zone about a desired gear position. In a second position, the lock member is out of engagement with the ring gear to permit rotation of the ring gear so that the adapter is rotated by internal forces of the transmission and the adapter automatically self-aligns to the exact desired gear position when the adapter is within the predetermined zone.