While cleaning my K&N drop in air filter this weekend I noticed the gasket is in really bad shape around the section of the stock air box that is removed when working on the air filter. The gasket is no longer attached to the box and is difficult to get to seat properly when closing the air box back up. It's also started to tear in one corner. I can't seem to find this part listed either at RockAuto or PartsGeek - both offer only a complete air box replacement. Does anyone know if I can buy one of these and replace the old one, or should I just pick up some weatherstripping and replace it with that?

 

i didnt know they had a gasket??

 

My factory box definitely has one. It's a rubber gasket around the perimeter of the box on the side that you remove. Most of it is still adhered very well to the box, but the bottom has collected some excess K&F filter oil over the years and that has caused the gasket to come away. I was actually surprised how much of the oil was on that gasket. I've always thought I was careful about not using a lot on the filter, but apparently I went overboard on a couple of occasions.

 

I'm a few months late on your thread, but I clean my K&N every August. I ran into the same issue on my '04 Intimidator. I noticed how the K&N oil was making it loose and harder to work with and this year mine got torn. I carefully put it pack together. My brother happened to be over and he thought the facorty gasket wasn't needed with the K&N filter and that's why it was a tight fit. So here I am trying to find an answer to question. Doesn't seem to be a common topic. I'll post a solution if I find one.