The K&N E-3322 is a round, high-flow replacement air filter built on K&N's washable cotton gauze media. The manufacturer lists it at 5.25 in. inside diameter, 6.25 in. outside diameter, and 2.5 in. overall height, and describes it as a universal-fit element. Its main advantage over a disposable paper filter is that it is cleaned and re-oiled instead of replaced. The manufacturer says it is engineered to last the life of the vehicle and carries a no-hassle lifetime limited warranty, so the purchase trades recurring filter costs for a one-time buy plus periodic cleaning.
Confirm that your housing's round opening matches these dimensions before ordering, since fitment information for this size varies between sources and the manufacturer should be consulted for application confirmation. Enthusiasts searching for a washable round K&N air filter, a reusable cotton gauze intake filter, or a 5.25 ID by 6.25 OD by 2.5 height element are usually looking for this exact size. Owners on user forums also stress that cotton gauze media should never be blown out with compressed air, which can damage the material.
The manufacturer's cleaning instructions call for K&N air filter cleaner and K&N filter oil only. The same instructions warn against gasoline, solvents, steam, and caustic cleaners.
Owners on user forums advise against it, noting that pressurized air can damage cotton gauze media. Tap loose debris out and wash the filter instead.
The manufacturer lists a No-Hassle Lifetime Limited warranty for this filter. Warranty descriptions vary across listings, so confirm the current terms with the manufacturer before relying on them.
Swapping this element into a round factory housing is a short job: open the air box, lift out the old filter, wipe the housing clean, and seat the K&N with its seal fully engaged. Cleaning and re-oiling follow the manufacturer's steps: spray K&N cleaner onto both sides and let it soak about 10 minutes without drying, rinse from the clean side with cool or warm water, and let it air dry. Then apply K&N filter oil evenly across the pleats until the media shows a uniform color. Do not tap the filter on its edges, and avoid pressure washers or high-pressure nozzles. Reinstall only when the element is dry or just slightly damp, and check the vehicle's own service information for any housing-specific steps. Tools needed: K&N cleaner, K&N filter oil, a tray or basin, a soft brush, and nitrile gloves.