I just took a look at my factory air filter on my 2005 at 7k miles and was surprised at how dirty it was. I have been on paved roads since day one. The fiberglass mat and "W" pleats in the filter media were packed with dirt and bugs.
My filter minder only showed less than 1/2 plugged. Needless to say I replaced it with a Fleetguard Filter from Geno's.
