K&N 33-2304 Air Filter

Replacement Filters / Replacement Air Filter
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$50.99 USD
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Product Overview

  • Designed to boost horsepower and rate of acceleration
  • Can be cleaned and used again
  • High air flow with exceptional filtration
  • Lasts up to 50,000 miles before cleaning is required depending on driving conditions
  • Works with original equipment manufacturer vehicle electronics
  • Emissions legal in all 50 US states
  • Will NOT void vehicle warranty
  • Million Mile Limited Warranty®
The K&N 33-2304 Air Filter fits some Chrysler 300C, Lancia Thema, Subaru B9 Tribeca, Subaru Crosstrek, Subaru Exiga, Subaru Forester, Subaru Forester Turbo, Subaru Impreza, Subaru Impreza II, Subaru Impreza II WRX, Subaru Impreza II WRX STI, Subaru Impreza III, Subaru Impreza III WRX STI, Subaru Impreza WRX, Subaru Impreza WRX STi, Subaru Legacy, Subaru Legacy GT, Subaru Legacy III, Subaru Legacy IV, Subaru Levorg, Subaru Liberty, Subaru Liberty Exiga, Subaru Outback, Subaru Outback II, Subaru Outback III, Subaru Outback XT, Subaru Tribeca, Subaru WRX, Subaru WRX STI, Subaru XV, and Subaru XV Crosstrek models. See vehicle applications link for details.
K&N's replacement air filters are designed to increase horsepower and acceleration while providing excellent filtration. We make over 1,200 different replacement air filters for the majority of vehicles on the road. These filters are washable and reusable and are custom designed to fit into your existing factory air box. Their drop-in design means adding performance is simple. With most vehicles you simply remove the disposable air filter and replace it with a K&N. See applicable instruction sheet for details. Our stock replacement air filters for street vehicles are covered by our famous K&N Million-Mile Limited Warranty and will be the last air filter your vehicle will ever need.

[More Information on K&N Replacement Air Filters]
Air Filter ShapePanel
Filter MaterialCotton Gauze
Height0.938 in (24 mm)
Outside Length8.75 in (222 mm)
Outside Width8.563 in (217 mm)
Package Contents1 Air Filter
Package Quantity1
Warranty1,000,000 Miles/10 Year
Product StylePanel Air Filter
Weight0.9 lb (0.4 kg)
Filter Re-Oiling Amount1.06 oz (31 ml)
Product Box Height11.56 in (294 mm)
Product Box Length10.44 in (265 mm)
Product Box Width1.75 in (44 mm)
WARNING: Cancer and reproductive

K&N 33-2304 Air Filter Product Reviews

Tuesday, February 5, 2019 - Part 33-2304
I'm seeing improvement in my gas mileage and the throttle feels more responsive.

David Nuckols
Dallas, Texas
Saturday, January 26, 2019 - Part 33-2304
To be honest I have often suspected that we're all kind of guilty of the placebo effect when we fit new parts However, I fitted this to my '09 Forester on a long weekend and didn't drive for two days. I then took the same route I do 6X days a week to work forgetting that I had fitted this product. I found my self speeding (slightly) and had to re-adjust my throttle input/speed a few times which was unusual as I drive this route regularly I then remembered I had fitted this Air Filter and couldn't help but believe it had actually made a noticeable difference Also, whilst not a HUGE difference, my average fuel consumption had also decreased by .2 L/100km (even after a wide open throttle test in second and third gear on the highway). Another added bonus is the improved induction sound. Looking to purchase one for my partners car now.

Michael Winfield
Wednesday, January 23, 2019 - Part 33-2304
Bought a filter to replace the one in my 163k mile 2008 Subaru WRX that the previous owner let go to the wayside. Filter lost its color, and was some of the rows were bent (wasn't seated in the air box correctly by said owner). Still never had any issues out of it. Love that it's washable. I can take it out every few months, rinse it, and throw it back in. Also have one of their cone air filters on my 2nd vehicle.

Rustburg, Virginia