Castrol will have Heavy Duty oils that meet the new CK-4 specification; the products that will meet CK-4 are CRB Multi 15W-40 CK-4, Vecton 15W-40 CK-4 and Vecton 10W-30 CK-4.

You are correct that Ford will not recommend the use of CK-4 oils. It is my underst... Login to read more.