Abstract: An internal combustion engine has an engine-braking master piston for a first cylinder actuated by a first rocker arm which, in turn, is actuated by the inlet push rod of another cylinder and an exhaust-gas-recirculation master piston is provided which is actuated by a second rocker arm which, in turn, is actuated by the exhaust push rod of another cylinder. An oil passage selector valve is provided for selectively switching over the hydraulic pressures produced by the engine-braking master piston and exhaust-gas-recirculation master piston to an oil passage to actuate a slave piston and open an exhaust valve of the first cylinder. To effect engine braking, the exhaust valve of the first cylinder opens as the piston is near its top dead center position at the end of the compression stroke or at the beginning of the expansion stroke.