Riffraff Diesel 6637 Filter Kit

Part Number:



Riffraff Diesel 6637 7.3L Intake Filter Kit

This kit contains: 

- Donaldson 6637 Filter
    - Optional AFe Big Boost washable, or a Donaldson Blue® Filters
- Custom "Riffraff Diesel" Pre-filter Cover (Optional $35)
- Powder Coated Adapter Tube 
    - 94-Early 99 Uses a 45* Mandrel Bent Tube
    - Late 99-03 Uses a straight Tube
- SS T-Bolt Clamp


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  • 5
    Improved performance

    Posted by Tyler on Sep 11th 2019

    I bought the donaldson blue with early 99 elbow, over stock this kit performs fantastic and lets the truck breathe. Strongly recommend.

  • 5
    6637 Filter Kit

    Posted by Tom B on Sep 9th 2019

    This is good quality. I had a Tymar system installed on my truck when I bought it (same filter). Things were looking a bit worn and corroded so I bought this kit. The elbow for my 96 7.3L is not long radius like the Tymar unit, so this setup is a bit short and the elbow hits my master cylinder. However, it is an acceptable fit. Also, this kit costs less than just the filter at Napa, so I am happy.

  • 4
    Filter kit

    Posted by Unknown on Sep 8th 2019

    Filter kit worked great, the customer service coming from this company is litteraly the best I’ve ever experienced. Friendly and quick to fix a mistake on my end with out hesitation. Will defiantly be coming back

  • 5
    Great quality

    Posted by Thomas Tracey on Sep 8th 2019

    Great quality product. Shipped to me quicker than expected. Installed in about five minutes. And is works amazing

  • 5
    6637 filter kit

    Posted by t. wayman on Sep 6th 2019

    This is an easy to install kit. The filter looks like it is 4x more area for the air to go through vs the stock setup. Good, quality parts included make this an easy way to add an open element filter. I did notice a lot more vibration through my brake pedal, but I have not trimmed up any of the lower panel that goes around the driver's side battery yet, so the filter rests up against the brake master cylinder. I plan to trim it up soon.

  • 5
    6637 kit with Donaldson filter

    Posted by The Dude on Sep 4th 2019

    My initial impressions are this is a great product and the service from Riffraff was exceptional; no complaints. I have less than 1,000 miles on the kit so far, so I'll have to update this review later on longevity, but at this price, I couldn't be more pleased.

  • 5
    Great 6637 kit

    Posted by Justin on Sep 2nd 2019

    High quality kit the 45° is powder coated steel, high quality filter(s) by Donaldson, they didn't even cheap out on the clamp (which they should sell separately and in different sizes for other uses). Everything fit perfectly

  • 5
    Filter kit

    Posted by Rob Wold on Jul 31st 2019

    Well thought out. Everything needed to complete the install without the crazy high price of some of the other kits

  • 5

    Posted by Andrew Ambs on Jul 30th 2019

    This filter is massive. Coupled with the 4" straight pipe my truck feels more responsive and less like a turtle. Was very pleased that the coupler is powder coated metal.