A telescopable shaft assembly has at least two shaft elements capable of sliding in one another as an internal shaft element and an outer shaft element connected to one another in torque transmitting manner via at least one sliding splined portion. An axial fixation defines predetermined breaking point between the shaft elements. The axial fixation becomes ineffective once a predetermined impact force acting in a telescoping direction is reached. The shaft elements are movable relative to one another, once the axial fixation has become ineffective, in low-friction manner along the sliding splined portion under the action of the impact force. When the axial fixation is effective, an annular gap is formed between a splined portion runout on a free end of the outer shaft element and an unsplined portion of the inner shaft element. The annular gap, at least in the area of the free end of the outer shaft element, is at least partially filled with a sealant.