Just to throw this out there i have used K&N Drop in filters on my 97,04, F-150 I have had No problems at all with the oil affecting my MAS, I just make sure to wipe the filter down after oiling to ensure.On another note if your concerned about filter efficency and you just hate to "oil" your filter i would suggest a Volant Power core CAI. A buddy just had one installed on his 2009 f150(5.4) and just to clarify this system is a sealed unit with air flow coming from the factory hole near the fender/ and also coming from the front where you can add the "scoop" upgrade. Im sold on the idea of getting a Volant if i go to a CAI i like the sound lol of course i also like the sound of nitto mud grapplers over my radio
