A hydraulic unit for industrial trucks, comprising a motor pump unit which is directly attached to a tank, a reflux filter which has an elongate filter casing for a filtering element adapted to be introduced into the tank through an opening, a hose coupling, and an outlet opening, wherein the filtering element is disposed in the flow path between the hose coupling and the outlet opening, a reflux hose between the motor pump unit and the hose coupling, and a closure for the reflux filter, wherein the reflux hose extends within the tank and the hose coupling is disposed within the tank.