A power drill has a housing holding a planetary gear transmission and a motor. A drive stem rotatable in the housing about the axis is rotationally coupled to the planet carrier, and a chuck body is rotatable on the housing. A driver axially bearing on the jaws is axially shiftable to position jaws in the chuck, and a sleeve threaded to the driver is rotatable to position the jaws in the chuck body. The drive stem can be coupled either to the chuck body for rotating a tool held by the jaws in a screw or drill mode or to the sleeve in a tighten/loosen mode for tool exchange. A first spring bears axially inward against a front face of the transmission ring gear with an adjustable axially inwardly directed force, and a second spring bears axially against a rear face of the ring gear.