So, I take my '05 GT to the "local" dealer for an oil change.(as long as it's under warranty, I want to pay someone to change the oil, an I'd rather have a dealer do it, rather than Jiffy, etc). The service advisor chickie tells me that it's $44 for the oil change and "I would advise you to remove that K&N air filter. It doesn't do the job. Ford denied a warranty claim on a diesel due to a K&N air filter". She said nothing about the JLT intake that the S&B (not K&N ) filter was attached to. Actually, I don't think that she actually looked at the car.

When I go to S&B's or K&N's web sit, they just quote the Magnuson-Moss Warranty Act. But do their filters meet OEM requirements for filtration?? What filter does Ford Racing use on their CAI. Does Fords CAI mantain new car warranty??

 

Was the warranty claim on your diesel ?? If so what was the problem? Dealerships are idiots most of the time and spew the void warranty statement WAY too often.
To avoid future problems, take it to another service center if there is one close.

 

I normally take it to the dealer that I purchased my car from, with no comments. My concern is with the filtering performance of an oiled-cloth type filter. Do they filter well enough to maintain OE standards.

 

If its letting more air through, its not filtering as well as a OE or paper filter would. The oil used isnt tacky either so particulates in the air aren't going to cling to it very well. I have a Amsoil filter on my Mustang that uses a tacky type of filter oil(has polymers in it) that will hold on to the dirt moreso than just plain mineral oil.
In my new car I plan on sticking with the OE filter.