An oil cooling system for an engine includes an oil input line configured to receive heated oil from a component, an oil cooler configured to cool oil and direct oil to an oil return line and a first bypass line configured to selectively bypass oil from the input line to the return line without passing through the oil cooler. The first bypass line includes a first oil pressure actuated valve urged toward a closed position, and configured to move toward an open position where a pressure differential across the valve exceeds first predetermined pressure. The first bypass line further includes a second oil pressure actuated valve urged toward an open position, and configured to move toward a closed position where pressure differential across the valve exceeds a second predetermined pressure. The second predetermined pressure is greater than first predetermined pressure, and the first and second valves are provided in series.