Duragard Diamond Plate Synthetic Blend CK4 10w30 Engine Oil - 5 Gallon Pail - Meets Ford WSS-M2C171-F1 Exceeds warranty requirements of engine manufacturers that require a type API CK-4/SM premium synthetic blend SAE 10W-30 motor oil. Resists fluid breakdown better at high loads and temperatures while providing much easier starting at low temperatures. Low ash detergency combined with super-dispersion action controls engine deposits and soot to maintain cleaner engines over extended oil change intervals. Meets Fords stringent 2017 and newer WSS-M2C171-F1 specification. Backwards compatible for all engines currently requiring CJ-4