Abstract: A gear pump in which one rotating, toothed pump gear is supported axially displaceable in the pump casing and engaging an axially displaceable sliding part at least on the one face wall of the pump gear. The sliding part is adapted to overlap the operating space or zone of engagement of the displaceable pump gear against the other, axially stationary pump gear, with hydraulic relief provided by the pump casing and/or the sliding part by pocket-like recesses on the side diametrically opposing the pressure side of the pump across the displaceable pump gear, the recesses hydraulically communicating with the pressure side of the pump.