i have an 04 dakota with the 3.7, i just changed the oil using maxlife and a fram tough guard, i swore i'd never use a fram filter that was'nt an extra guard but i got a good deal on it as a package deal at autozone, now my engine is noisier then it use to be (before this lof) and i have a performax po-21 (made by purolator) that looking at the specs is the same only shorter, so i'm thinking about just swapping filters. i'm also concerned because i was looking at a graph of flow rates on a post on this site and the tough guard had the worst flow rates. anyone think swapping filters for the po-21 would be a bad idea?