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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 269 | Next

  1. A must have! 5 Star Review

    Posted by on Apr 10th 2018

    I recommend getting the pre filter as well. Looks cool and protects from dust well. Not too noisey in the cab and really helps with flow

  2. Nice air intake 5 Star Review

    Posted by on Apr 3rd 2018

    Mt stock filter housing cracked and dusted my turbo, To replace the stock intake box would have been stupid expensive even used. This Riffraff air intake was a lot cheaper, flows better, and looks a lot better then stock. Thanks.

  3. The whistle is real 5 Star Review

    Posted by on Mar 30th 2018

    Noticeable power improvement, can definitely hear the turbo now which is worth at least 50 more horsepower. Install was super easy, instant gratification, will be ordering more from RiffRaff soon.

  4. Huge Difference 5 Star Review

    Posted by on Mar 29th 2018

    Removed the Factory Air Box on my 2000 F250 7.3 Diesel and added the Donaldson Blue 6637. It installed easily and fit better after installing the Factory Driver Side Battery Tray (also purchased at Riffraff Diesel at a great price). I noticed an immediate increase in mileage and when I jumped on the turbo to make a lane change, I couldn't believe how well the old girl woke up! Push you back in your seat -- kind of improvement. I need to put a take or two more through her but I am getting more miles between fill-ups. Thanks Riffraff...

  5. Better thank stock 5 Star Review

    Posted by on Mar 28th 2018

    Good product. Just wish the shipping wasn't so expensive.

  6. Easy small boost in power 5 Star Review

    Posted by on Mar 28th 2018

    My 6637 kit went on a late 99 7.3. I got what I was expecting...very easy install, and small boost in throttle response and power. Any noticeable increase is worth this price tag in my opinion. Also as an extra little bonus, you get some cool new sounds from under the hood. Well worth it.

  7. Awesome filter kit 5 Star Review

    Posted by on Mar 19th 2018

    Easy enough to find a piece of 4” to adapt filter to stock intake. But this kit has it all included already. Got the donaldson blue filter and optional filter cover to prolong filter life. Installs easy and does exactly what needs to be done.

  8. Well worth the money 5 Star Review

    Posted by on Mar 8th 2018

    If you are on the fence about replacing your stock air intake, it is a must. This is finally a air intake setup that gets my 7.3 the air it needs

  9. It whistles!!! 5 Star Review

    Posted by on Mar 5th 2018

    Does great. A bit loud but I'm a redneck so I enjoy being loud and obnoxious!

  10. Make sure you have OEM tube 5 Star Review

    Posted by on Mar 1st 2018

    I replaced my AFE Stage 2 Intake with this kit + the AFE Big Boost Filter

    Big improvement, at least in the cold months. Seems to let more air through, and better spool-up.

    HOWEVER: Make sure you have the OEM intake tube (Riff-raff also sells this if you don't have it). I had to reinstall my AFE Stage 2 after taking it out because the 6637 kit uses the oem rubber hose, which I did not have.

    I made a second order from Riff Raff, installed it in about 5 minutes, and its much better than the Stage 2.

Showing reviews 1-10 of 269 | Next