An engine oil system for an internal combustion engine comprises an electronic control module, an oil viscosity sensor, am engine oil cooler, and an oil cooler flow control valve. The oil viscosity sensor is disposed in communication with the electronic control module. The electronic control module determines a viscosity of oil within the engine oil system based upon an output of the oil viscosity sensor. The oil cooler flow control valve is disposed in communication with the electronic control module. The oil cooler flow control valve is positionable between an open and closed position to regulate coolant flow to the engine oil cooler based upon an output of the electronic control module. The electronic control module moves the oil cooler flow control valve based upon the determined viscosity of the oil.