Avoid abrasion and corrosion of your engine from dirt and debris by regularly replacing your Jeep's air filter. Having a clean air filter improves performance by allowing the correct amount of oxygen to flow through the engine. A dirt clogged air filter hampers performance by blocking the free flow of air. If your Jeep's gas mileage is decreasing, if the engine is misfiring or if you are hearing vibrating, coughing or slipping sounds when you're idling, these could be signs of a dirty air filter. You'll find a wide variety of performance air filters for any Jeep application on 4WD.