Ok I need to say this one more time. I do Diesels, fast Diesels and we stopped running the K&N filters. No matter how much oil you put on them the dust will get through. I have Blackstone Lab test our oil after we race. The number one contaminant is Dirt/Dust. Now a turbo charged Diesel will pull way more air than this thing could ever pull, but when you put that much money in to a motor you need all the info you can get. Just be care full you need to look IN the filter (not the outside) the inside. If it's dusty where you are riding clean it every time. K&N's are just an air filter you can wash over and over that's all nothing special. In this application you need to run a cover you have to run a cover. I don't profess to know every thing just what I have seen in what I do. What we run now you can't run on this thing unless you don't want a passenger