A power telescoping external vehicle rearview assembly comprising a drive gear assembly for telescopically moving a rearview head between a retracted and an extended position is disclosed. An embodiment of the rearview assembly comprises a bracket mountable to a vehicle, a rearview head telescopically mounted to the bracket via a plurality of arm assemblies, a rearview element mounted to the rearview head, an electric motor mounted to the rearview head, and a gear assembly connected between the motor and the plurality of arm assemblies. An embodiment of the gear assembly comprises pinion drive gear assemblies with rolling clutches for selectively disengaging the motor from the arm assemblies, a fixed clutch assembly for transferring power from the motor to the pinion drive gear assemblies, and a drive shaft connecting the fixed clutch assembly to the pinion drive gear assemblies.