A freewheel for changing a transmission characteristic of a planetary transmission for a motor vehicle transmission. The freewheel has a first ring which has a first blocking contour, a second ring which is rotatable relative to the first ring and which has a second blocking contour, tiltable blocking bodies which can be caused to engage into the first blocking contour and into the second blocking contour, and a switching element for tilting the blocking bodies. The switching element, in a blocking position, clamps the blocking bodies immovably to the first blocking contour and to the second blocking contour, in a freewheel position, allows unidirectional freewheeling, and in an inactive position, holds the blocking bodies down on the first ring so as to be spaced apart from the second ring.