A vehicular exterior rearview mirror assembly includes a mirror head movable relative to a mounting base between an extended position and a folded position. An actuator is electrically operable to move the mirror head between the folded and extended positions. A pivot tube extends from the mounting base and through a base portion of the actuator. The pivot tube includes a tapered portion at least partially received at a channel of the mounting base. An inner surface of the channel includes a shape that corresponds to a shape of an outer surface of the tapered portion. A biasing element disposed between a housing of the actuator and an upper end of the pivot tube biases the tapered portion toward engagement with the inner surface of the mounting base along the channel.

Claims data not available