Hey PREME,

A "K&N" filter, or stainless steel mesh filter, will theoretically last forever, as long as you keep it clean. The longer you wait in between cleaning it, the more the mesh will corrode over time. However, I clean mine every oil change. It is important to not use anything too harsh to clean it.

For example, I use "Murphy's Oil Soap", which funny enough, is a wood floor cleaner. Sounds weird, but it is all natural and extremely gentle, yet it really cuts through grease very well. I also suggest also using it for cleaning/de-greasing your engine bay. Just put like an inch or two of Murphy's in a spray bottle, fill the rest with water, and spray the shiz out of the entire engine bay. Let it sit for 5-10 min, and rinse it all off! It cleans very thoroughly, without drying out rubber parts and without leaving any greasy residue like some other products. Plus, it leaves an awesome smell that further unlocks as the car heats up, you can smell it as you drive along for the first 50-100 miles, lol. Anyway, same technique with the air filter. De-grease & rinse well.

HOWEVER, MOST IMPORTANTLY, THE AIR FILTER MUST BE BONE DRY BEFORE PUTTING IT BACK ON. Don't use compressed air, just let it dry very well in the sun. Some filters are "dry" filters and others are "wet", meaning they require a special, aerosol-ed oil to be sprayed on them before reinstalling. For example, "K&N" brand filters are wet, and you can purchase their "K&N Air Filter Oil" kits. If the filter is a "wet" type, just spray a light coating on the exterior of the filter. Ask the manufacturer of whatever system you choose, whether the filter is "dry" or "wet".

Good Luck. Drive Safe & Drive Often. Rubber Side Down. Over & Out.