Hydraulic piston consisting of a cylindrical body housed with a small clearance in a cylinder, said piston being capable to translate in said cylinder with which it forms a hydraulic chamber of variable volume, a first end of said piston having a compression surface opening into the hydraulic chamber for receiving the pressure of a fluid, while the other end of said piston has a piston support surface for exerting a force on transmission means, said piston comprising: • At least one cooling and lubricating gasket valve positioned on the side of the compression surface and in the extension of the cylindrical body relative to which it can move in longitudinal translation over a short stroke, said valve comprising, firstly, a piston-side valve axial surface which has a circular flow closure surface which can come into contact with a valve contact surface provided on the compression surface, said valve having, secondly, an cylindrical external valve surface which exposes sealing means which can sealingly come into contact with the cylinder, said valve comprising, thirdly, a chamber-side axial valve surface which faces the hydraulic chamber; • At least one intermediate fluid outlet chamber formed - within the circular flow closure surface - by the piston-side valve axial surface and by the compression surface; • At least one flow calibration opening which passes through the cooling and lubricating gasket valve mainly in the axial direction, the hydraulic chamber communicating with the intermediate fluid outlet chamber via said opening, and • At least one valve abutment-link which connects the cooling and lubricating gasket valve to the cylindrical body, said abutment-link allowing said valve to come closer to said body to the point that the circular flow closure surface contacts with the valve contact surface, while said abutment-link prevents said valve from moving away from said body more than a certain distance; Said piston being characterized in that it comprises: • At least one valve return spring which tends to move the cooling and lubricating gasket valve away from the cylindrical body. • At least one cooling and lubricating gasket valve positioned on the side of the compression surface and in the extension of the cylindrical body relative to which it can move in longitudinal translation over a short stroke, said valve comprising, firstly, a piston-side valve axial surface which has a circular flow closure surface which can come into contact with a valve contact surface provided on the compression surface, said valve having, secondly, an cylindrical external valve surface which exposes sealing means which can sealingly come into contact with the cylinder, said valve comprising, thirdly, a chamber-side axial valve surface which faces the hydraulic chamber; • At least one intermediate fluid outlet chamber formed - within the circular flow closure surface - by the piston-side valve axial surface and by the compression surface; • At least one flow calibration opening which passes through the cooling and lubricating gasket valve mainly in the axial direction, the hydraulic chamber communicating with the intermediate fluid outlet chamber via said opening, and • At least one valve abutment-link which connects the cooling and lubricating gasket valve to the cylindrical body, said abutment-link allowing said valve to come closer to said body to the point that the circular flow closure surface contacts with the valve contact surface, while said abutment-link prevents said valve from moving away from said body more than a certain distance; • At least one valve return spring which tends to move the cooling and lubricating gasket valve away from the cylindrical body.