Valve train system for an internal combustion engine

A valve train system for an internal combustion engine includes an exhaust valve moveable between an exhaust closed position and an exhaust open position. A camshaft includes a main exhaust lobe for moving the exhaust valve between the exhaust closed position and the exhaust open position for expelling exhaust constituents from the combustion chamber and an exhaust rebreath lobe for moving the exhaust valve between the exhaust closed position and the exhaust open position for allowing exhaust constituents into the combustion chamber. A two-step device is provided for transmitting motion from the camshaft to the exhaust valve and is switchable between a motion transmitting position and a motion preventing position such that the motion transmitting position allows motion to be transmitted from the exhaust rebreath lobe to the exhaust valve and the motion preventing position prevents motion from being transmitted from the exhaust rebreath lobe to the exhaust valve.