K&N filters
Anyone changed there factory air filter to K&N?If so was it worth the cost i.e. improved mileage?
Forum Discussion
My experience with K&N is they let a lot of fine dust through. I tossed mine in the trash after seeing that. I have also seen dyno tests done where a 2004/5 5.9L Cummins was the test mule. Clean paper filter vs about 7 aftermarket whiz bank kits. Max hp difference was 1 hp + or - which is likely within the error margins of the test.
