Figit090 said:I figure WIX is better because one-its more expensive, two-i couldnt get it at k-mart. three-it wasnt at kragen four-it has a little spring just inside the opening, and whatever that does, it must be better than the Bosh because the bosh didnt have that. bypass valve maybe? not sure how they work, but its extra parts, extra assembly, (more money) and wouldnt be there unless it was a better quality filter. plus, it was larger than the fram, most likely meaning better filtering surface area.
I cant say which is better beyond that because i have never payed for oil analysis, or cut open my filters to look at the insides. from my observations however, WIX is the best out of the ones i've had.
LOL...don't exactly use this logic myself when buying a filter, but the Wix is a very good design. That spring valve you saw is a bypass valve designed to allow oil to continue to flow if the filter clogs or if flow exceeds filter capacity. The Wix has it at the opening of the filter, most others have it inside near the dome at the top. The advantage is if the Wix goes into bypass, you don't have the oil going through the filter at all and picking up contaminates.
Both the Wix and PureOne have very good anti-drain valves as well. The PureOne filter media is finer and has more pleats than a Wix so it does filter a bit better. Either is an excellent choice IMO.
Don't knock a filter because some of the discount stores sell them. The SuperTech WalMart sells is actually a darn good filter...heck of a lot better than a Fram.
Grim - You are correct, the Napa Gold is a Wix filter.