Perfect fit to replace my worn out element on my K&N intake. Its nice to have the better filter quality from the 6637 filter at a great price.

You can hear your turbo very clearly with this, especially the blow off valve, which is nice but you also hear additional engine noises which perhaps are not so enjoyable.

Its the cheapest alternative if youre running a chip and need more air, but you'll pay for it with more noise.

Truck runs great with this filter.
Riffraff's fast shipping is awesome.
Best price to!
Thanks for all your teams effort Clay.

This product was just what I wanted. It did not take that long to get here every thing went well.

Riffraffs 6637 air filter kit is the best bang for your buck hands down. I bought their full kit for my 99 7.3 ford and it was a breeze to install. I also purchased the filter and cover for my 2nd gen Cummins diesel and it made a very noticeable difference. I wouldn't hesitate to install this filter on any diesel in the future.

I put this filter on my 6.0 and it works great! I just bought a long 3" 90 degree pvc pipe and a ring clamp and clamped on end to the filter and the other to the rubber hose on my intake. it was a tight fit but I love it and plan to get the washable one soon. cant beat the flow and value.

I don't have to worry sand blasting my turbo any more. Very easy to install. The best customer service ever.

Product is high quality and very fast shipping. Great business and great guy. Recommend for anything u need. Have ordered a few times now and its always this way.

Love this air cleaner ! Did a DIY intake on my diesel 7.3. Can't beat the price anywhere ! Works awesome