A valve train assembly comprising an exhaust valve rocker arm assembly selectively opening first and second exhaust valves (28, 26) and comprising: an exhaust rocker arm; and a valve bridge operably associated with the rocker arm and including a main body, the main body configured to engage the first exhaust valve, the valve train assembly further comprising an engine brake rocker arm assembly comprising an actuator assembly; characterized by: the valve bridge comprising a lever rotatably coupled to the main body of the valve bridge,); wherein the engine brake rocker arm assembly comprises an engine brake rocker arm which is configured to rotate the lever to open the second exhaust valve, and wherein the actuator assembly is coupled to the engine brake rocker arm and wherein the actuator assembly is movable between a retracted position and an extended position, wherein in the retracted position the actuator assembly does not engage the lever, and in the extended position the actuator assembly selectively engages the lever. an exhaust rocker arm; and a valve bridge operably associated with the rocker arm and including a main body, the main body configured to engage the first exhaust valve, the valve train assembly further comprising an engine brake rocker arm assembly comprising an actuator assembly; characterized by: the valve bridge comprising a lever rotatably coupled to the main body of the valve bridge,); wherein the engine brake rocker arm assembly comprises an engine brake rocker arm which is configured to rotate the lever to open the second exhaust valve, and wherein the actuator assembly is coupled to the engine brake rocker arm and wherein the actuator assembly is movable between a retracted position and an extended position, wherein in the retracted position the actuator assembly does not engage the lever, and in the extended position the actuator assembly selectively engages the lever. the valve train assembly further comprising an engine brake rocker arm assembly comprising an actuator assembly; characterized by: the valve bridge comprising a lever rotatably coupled to the main body of the valve bridge,); wherein the engine brake rocker arm assembly comprises an engine brake rocker arm which is configured to rotate the lever to open the second exhaust valve, and wherein the actuator assembly is coupled to the engine brake rocker arm and wherein the actuator assembly is movable between a retracted position and an extended position, wherein in the retracted position the actuator assembly does not engage the lever, and in the extended position the actuator assembly selectively engages the lever. the valve bridge comprising a lever rotatably coupled to the main body of the valve bridge,); wherein the engine brake rocker arm assembly comprises an engine brake rocker arm which is configured to rotate the lever to open the second exhaust valve, and wherein the actuator assembly is coupled to the engine brake rocker arm and wherein the actuator assembly is movable between a retracted position and an extended position, wherein in the retracted position the actuator assembly does not engage the lever, and in the extended position the actuator assembly selectively engages the lever.