I was just wondering what types of oil filters most of you use on your machines. I have always used Fram oil filters. And I have never really had any problems. But a local Auto store had out an oil filter test display, and surprisingly Fram actually tested the worst out of any of the other filters. The best was STP. So I asked a few people I know that our heavily into cars. And no one seemed to think that Fram was a good filter. Anyways, so this has got me considering switching filter brands. I may try STP. Has anyone tried any of the generic filters they have been selling? I know both Advance Auto and Wall Mart have their own brand now. They seem to be much cheaper than the brand names. So what filters do you all use? And can anyone knowledgable out there explain to me what the difference in filtration is between a good and bad filter?