Tue but I got by what oil analysis people say (never dealers) and so far, they are right with there suggustions for my auto (AMsoil, K&N or Mobil filters). If wears are within 10% a pass bypass spring does not matter. It matters if your engine is dirty as hell and it blugs (never had that issue yet). Heck, I can use a lesser filter and LC20 in Amsoil and perform better then 2 out of 3 filter above.Just to keep the record straight.....AMSOIL EA Series Automotive and MotorCycle Filters are ASSEMBLED mostly by WIX, not made by them. The internal parts come from several souces. Donaldson does manufacture the Patented Media used in the EA filters but the Donaldson Automotive filters do not use this material by contractual agreement. It is ONLY available to AMSOIL.
The K&N does have a good Micron Rating although not as good as the AMSOIL Filters. The problem I see with the K&N is they utilize compressed cellulose media... Imagine the media like this... Take corrogated cardboard... it is a huge wick for any moisture... now compress it and it basically becomes a brown paper bag.. The bag has a slicker surface and will not hold the contaminants as well allowing them to fall off and back into the system.. just my observation.
The Mobil 1 filter is a good filter but I don't like the use of a stamped steel by-pass spring.. I would opt for the WIX ..
Do not get me wrong I think Amsoil is a great oil but not needed in some apps and they do not get the lowest wears in all apps either. Now with brake fluid and PS fluid it going a little nuts. I might by it just to see for $5.20 PC price.
Reason why I dislike it; I used Amsoil from day 1 in cars, diesels etc for years. Then tried Lc20 and wears came back WAY better and this product cleaned better then anything to date. That was the #1 selling point for Lc20 and a "hit" on Amsoil. Amsoil's 25K mile is a crap shoot. Even TS will tell you that and even how they came up with it. Lastly, is there shipping is a joke. I can order a spark plug and its weight is 1 lb but a qts is what?