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aFe Air Filter, 4" F x 8.5 B x 8.5 T x 11 L, Pro 5 R (BHAF)

A better option when building a BHAF than the 6637, the AFE Big Boost air filter is washable and flows significantly more air. Air Filter has 4" Flange, 8.5" Base, 8.5" Top, and is 11" Long. With five layers of progressively finer mesh cotton gauze media between 100% polyurethane top and base, this high flow “oiled” conical performance filter provides excellent airflow for maximum horsepower and torque. Washable and reusable for multiple cleanings, the tall, open, evenly spaced pleats provide excellent dust holding capacity for longer service cycle between cleanings. Pliable polyurethane flange with integrated bumps insures tight, no leak seal over the life of the filter.
Was: $123.14
Sale: $103.00
Save: 16%
Save: $20.14
5 5 2

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  • 24-91042
  • 24-91042
  • 802959242643
  • aFe
  • New


Shipping Information

  • Item Requires Shipping
  • 4.0 lbs.
  • W15.0000” x H10.0000” x L10.0000”
  • Free Shipping

Customer Reviews

Comment Total Reviews (2)

Sounds and Feels better than 6637
  • Currently 5/5 Stars

Reviewed by:

Product ownership: Less than 1 month

Purchased from: KT Performance

The sound alone this filter allows makes it worth it to own. Truck feels like it revs slighty quicker though this my be in my head and instead of topping out around 18psi I can get a little over 20psi if I floor it on the highway. I am interested to see if MPGs or anything else changes in the future.

  • Currently 5/5 Stars

Reviewed by:

Product ownership: A year or longer

Purchased from: KT Performance

I definitely prefer this filter to the Donaldson equivalent. I have swapped back and forth between the two a couple times and now only keep the Donaldson to put in while I clean the AFE filter. The truck feels like it has better response and my mileage tracking on my phone shows that I am getting slightly better mileage, especially on the highway with the AFE. I know that I have read where people say their is no difference and how whatever they run is the best, but I have been tracking my mileage on my phone for several years and I have looked at the data for times when I had the two different filters in and was running the same trip on the same roads on cruise control and my data seems to support this filter being an improvement.

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