I own a 2008 Super Duty and belong to several forums and I'm constantly reading about warranty denials for one thing or another, oil being one of them along with emissions issues. Ford is a real humdinger when it comes to denying warranties. Personally, I'm waiting until my warranty is out before straying too far from stock. We can all offer all sorts of opinions and quote all kinds of legal precedents but when it comes right down to it, Ford has us by the cajones. It's "Who's right, who's wrong and who holds the warranty". Just my 2 cents.