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Riffraff Diesel Performance Inc, Engines - Supplies, Equipment & Parts, Eagle Point, OR


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Riffraff Diesel 6637 Filter Kit

  • Late 99.5-03 Kit
  • 94-Early 99 Kit
  • Donaldson Standard Cellulose
  • Donaldson Blue® Filter
  • AFe Big Boost Filter
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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Product Reviews

Showing reviews 1-10 of 293 | Next

  1. GREAT UPGRADE! 5 Star Review

    Posted by on Oct 4th 2018

    1995 7.3 92,000mi
    Works great! It fits perfectly and looks great with the black dust cover. Remove old air box and kept it since you can hardly find the factory air boxes for under 200 dollars. Didnt hear any turbo noise change but the truck already had 4 inch exhaust straight with a 7 inch tip. Opened up the exhaust so I had to give the truck more air! Love this upgrade and will buy all my filters from riffraff from now on!

  2. Great Fit 5 Star Review

    Posted by on Sep 12th 2018

    I needed a new air filter for my 1997 7.3 and didn't want to spend an arm and a leg on a Cold Air kit that may only provide slight gains. This kit was very affordable and easy to install, plus I can make modifications like a heat shield later

  3. Excellent product, donaldson blue made exclusivley for Riff Raff.. 5 Star Review

    Posted by on Sep 9th 2018

    Very happy with filter... Excellent filtration, fit , performance,as well as look..

  4. Honest service and high quality parts 5 Star Review

    Posted by on Sep 8th 2018

    I have a late 99 7.3. It is stock /195k. Always had excellent care and service. I purchased the 6637 kit because my stock filter box was not sealing good any more. This kit fits perfect with the new battery tray. I recommend the new tray as a must! Cleans up the driver side a bunch and let filter sit correctly. As far as performance goes , I did not see huge power or fuel mileage gains. That’s what tuners , bigger injectors , turbos and bigger exhaust are for. Having said that I conclude this kit does exactly what it is designed for. Keep dirt out of the turbo while allowing clean air in. One other product that is Awesome is the HPX. World of improvement in starting and smooth running!!!

  5. Very Simple 5 Star Review

    Posted by on Aug 29th 2018

    Product works as intended, really easy install, and truck seemed to pick up a little faster than before and I now know there is a turbo. Order was fast.

  6. Fit as advertised 5 Star Review

    Posted by on Aug 21st 2018

    Order came in a timely manner - no problems

  7. Filter hits the hood 4 Star Review

    Posted by on Aug 11th 2018

    I read all the reviews and knew going into this that the hood would hit the filter but I didn't realize how much though. I didn't want to force the hood closed so I got out a cutoff wheel and modified the stock filter base to allow it to sit low enough to clear the hood. I figured I wouldn't go back to the stock filter housing so might as well make the new filter fit right. Hopefully it will have been worth it.

  8. Only buy replacement filters from RIFFRAFF 5 Star Review

    Posted by on Aug 3rd 2018

    Bought Riffraff Diesel 6637 Filter Kit 3 years ago and replaced the filter with a new Napa gold. BIG mistake run over a water puddle and sucked in the filter. The paper of the filter wiped out the turbo and plugged up the intercooler. Driving off road $2000.00. Fun in the dirt priceless.

  9. A whole lot better than stock 5 Star Review

    Posted by on Jul 24th 2018

    Dropped right in 96 F350 crew without any problems. Already experienced better throttle response & mileage going to the same places as before. Idle has gotten slightly better.

    Females mechanics should find the only extra tool they need is a ladder.

  10. Air filter 5 Star Review

    Posted by on Jul 1st 2018

    Just finished putting this on my stock 2002. Have not driven with it yet. I feel very confident in using the Donaldson filter and for $60 for the kit it’s a very good deal. I had to trim of the bottom of the old air filter base to get everything to fit under the hood. Only took a few minutes with a cutoff tool, no big deal. Was fairly simple to install. I only wish it would have came with instructions. As usual, parts were Riffraff quality (the best) and only reaffirms my habit of shopping Riffraff first.

Showing reviews 1-10 of 293 | Next