This is from another message board that I'm a member of.The moderator there had this problem with his Powerstroke: I took the F250 to the dealership for an oil leak today that turned out to be the result of a Wix (Napa Gold) oil filter. I changed the oil just prior to my NC trip and upon returning I noticed a leak under it. I crawled under it and saw that it was coming from the top of the motor leaking down the back from the area where the Turbo stand is. It's under warranty so I just took it in to the dealer. They called me and told me the filter housing was leaking like a sieve. It's a recessed o-ring seal in an alum. housing that is just tightened until it bottoms out. There should be no way it would leak and I've changed it a dozen times before. The dealer told me he has had 4 trucks in over the last 2 weeks with the same problem. All have had the redesigned Wix filter that includes the filter cap. A new Motorcraft filter and filter cap and it's fixed. I've never, ever had a problem with Wix filters, but a quick google search turned up some stuff and there was an internal memo about it that the service writer mentioned. I've also seen some reference to a problem with the fuel filters. Apparently there is a redesigned one for that as well and you can't mix and match the filters and filter caps or you'll have a nasty leak. Just letting you know.