Abstract: A power adjuster (30) for adjusting the position of an upper track (16) relative to a lower track (18) of a seat track assembly (10). The power adjuster includes a lead screw (22) fixedly secured to the upper track, a drive assembly (32) operatively coupled to the upper track and selectively coupled to the lead screw, a driven assembly (34) operatively coupled to the lead screw and selectively coupled to the drive assembly, and a release mechanism (36) coupled to the upper track. The release mechanism is operable between a locked condition coupling the driven assembly to the drive assembly and the upper track wherein the driven assembly and the drive assembly move longitudinally along the lead screw with the upper track relative to the lower track and an unlocked condition wherein the driven assembly is decoupled from the upper track and retained along the lead screw during movement of the upper track relative to the lower track.