I get my Motorcraft filter at Advance Auto for about $20 or less. Napa is charging $29 (WOW). I have not checked wal-mart yet, but will. I've also heard the wal-mart filters have a different part number on the box... something about ending in AB vs the AA. the ones I get from Advance are AA. Not sure what that all means either. I'm suprised theres not more people jumping on the Amsoil filters. seems like theres a lot of amsoil buffs around with these trucks. It's design (to me) looks like the wix filter design, with different elements.