Most ford dealers don’t use 10w30, they use 5w40. The logic is people that buy these trucks are using them to tow, which ford wants 5w40. Unless someone buys a super duty to just drive around uses 10w30, which is not to smart to buy one just to drive around.Also the 10w30 is for temps above freezing. In owners manual it states to use 5w40 in below 0 weather conditions. I even asked our Ford people near my work.