I've been using fram xtraguard and motorcraft filters mixing between both for 4 years now. I generally feel that the fram filters are heavier at the end of a 3k mile oil change than the motorcraft filters (after draining the oil from them of course). I just installed a purolator filter for the first time so we'll see how that goes.
This is what I found http://www.purolatorautofilters.com/...ilFilters.aspx
Anyone try royal purple oil filters?
A few years ago, I went to the gym for several months and lost 30 pounds. That must be worth about 1% more fuel economy in the city.