4. How often do I need to clean my K&N air filter?
If you have not experienced a decrease in mileage or engine performance, chances are your filter is fine and does not yet need cleaning. To be more specific, the filter does not require cleaning if you can still see the wire screen on the entire air filter regardless of how dirty it may appear. When the screen is no longer visible some place on the filter, it is time to clean it. When used in normal paved road, street or highway conditions, our replacement air filters that fit in the factory air box should require cleaning every 50,000 miles and our large conical filters on an intake system should require cleaning every 100,000 miles. When used in dusty or off-road environments, our filters will require cleaning more often. We recommend that you visually inspect your filter once every 25,000 miles to determine if the screen is still visible.
18. Can I use anything other than K&N cleaner and oil?
For best results, we recommend that you use K&N air filter oil and K&N air filter cleaner. K&N air filter oil is a special compound which forms a very efficient tacking agent that helps capture dust. Our cleaner is a non-detergent degreaser. Petroleum products such as transmission fluid and motor oil will soften and destroy the rubber sealing edges. Harsh solvents and gasoline will harden the rubber seals causing the filter to distort (shrink). A mild detergent can be used in a pinch, but care should be taken to fully rinse it out. Rinsing detergent out of a filter is similar to getting soap out of a sponge; it's not that easy to do. Always make sure the filter is dry before re-oiling.
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