[RayChez1]

K&N are good for gasoline engines, but I would not put one on a diesel. Mine originally come with a Farr air filter, didn't like it, not enough air for the turbo. So next I went to Napa and bought a Wix and the same problem, not enough air for the turbo. So after a lot of research I decided to try a Racor through the internet and wow what a difference in power and the vacuum gauge acted the way it is suppose to. Before with the other air filters the vacuum gauge would go up even with the new filters, so I knew the turbo was not getting enough air. I have the 3126-E Cat engine with is basically the same as the newer C-7 but with less emission controls on it.

Measure the ducts on the air filter coming out. One connects to the air coming in and one past the filter to the turbo. Then just match with what is shown on the website of Racor in the internet. I believe I paid around $120.00