The Controversy over using a K&N air filter in a 2015 Ford F-150
An F-150 owner touched off the firestorm, in the Ford F-150 forum, with a simple question. Kenny asked “K&N filter? Yes or No, Why?” Just a day later, he has received four pages of replies, some nice, some helpful and some that are quite dismissive. There is even one reply from K&N.
K&N markets their air filters as lasting forever with a little maintenance. They are more expensive than the disposable ones. They claim that their oiled filters catch more dust and dirt and allow vehicles to run better.
Benz was first to respond in a matter of minutes. He says “Oiled filters screw with the mass air flow sensor to say the least. There's no pros to outweigh the cons with a drop in K&N filter on a modern engine. Dry filters can be reused as well, mine is washable.”
CBR says “I am not a fan of K&N filters especially on turbo engines. S&B and AFE make some really good dry and cotton filters that perform very well and filter as good as stock.”
Another F-150 owner defends the K&N. “I've had a K&N on my Raptor for 6+ years. An oiled filter is only an issue if you don't know how to re-oil it. Too much oil can cause problems, but doing most things wrong causes problems.”
Bubba from Arizona says the increased air-flow is a non-issue. “For the price of a K&N oiled filter and recharge kit you could replace better filtering paper filters for the life of the truck. Regardless of co. claims and dyno charts you will not see any increase in performance on a turbo engine [ The turbo's compensate for any reduced air flow by simply turning faster the same way they compensate for higher elevation]. In the end the amount of air fed to the engine is controlled entirely by the ECM and the throttle body and the stock paper filter will flow much more air than the engine can use.”
Rick, from Michigan, issues a warning “Dozens of threads on this. Stay away, no upside, only problems.”
An Ohio driver says he learned his lesson the hard way. “I will never put another K&N oiled filer in any of my vehicles. I had a K&N CAI on my 2010 Mustang, Ended up having to replace the MAF sensor acouple of times, clean the whole intake system and replace the oil filer with a standard filter to fix my various CEL issues.”
K&N posted a lengthy statement on the Ford F-150 forum site. The company claims that dealerships bad-mouth the K&N because it stops them from selling more disposable air filters. The statement says, in part, “We are aware of the "urban myth" (K&N News Story) created by a few dealerships that a vehicle's MAF sensor can be contaminated by K&N filter oil. No evidence has ever been provided to support this "myth" and years of diagnostic testing by K&N has shown that not only is this allegation not real, it is not even possible. In our opinion, it is an excuse for a dealership and/or the vehicle manufacturer to avoid a legitimate warranty repair.”