I was at Walmart and they had 12 Shell branded oil filters for the Ford 6.0 diesel. I bought 4 of them as they had them marked down to $4.50 a piece. Who makes these and are they any good. Thought I would try them for that price. I just missed getting 4 Pennzoil 1.25 gal 0w-40 full syn jugs for $7.00 a piece. Watched the guy in front of me take all 4 of them.