A thrust piece unit for rack-and-pinion steering mechanisms, which is integrated into a housing bore of the steering mechanism housing of motor vehicles, in order to keep the pinion in constant intermeshing with the rack, the thrust piece unit comprising a cylinder part, a piston part and two chambers which are matched with one another and are filled with hydraulic medium and which are connected to one another via a replenishing valve and via a throttle point, and overload protection being additionally integrated in the thrust piece unit.