Ford Specs Motorcraft 5w-20 Super Premium. I want to stay with a mineral based oil since I change it every 3K miles and my car generally gets light duty driving. Is any high quality oil such as Castrol 5w-20 equal to the Motorcraft Super Premium. I have never had problems on other vehicles with using a standard high grade oil as recommended by the manufacturer. It appears that a synthetic has possibly caused some excess oil consumption according to earlier posts. I don't know if it has been proven to be caused by the properties of the synthetic oil but I see the use of a synthetic as an unnecessary cost for the cobra engine. Does anyone know Ford's position on oil other than what they specify? Thanks in advance