K&N Performance Cold Air Intake Kit 57-1518 with Lifetime Filter for 1996-2001 Jeep Cherokee 4.0L Estimated horsepower gain of 7.9 HP at 4511 RPM Designed to improve throttle response and engine sound Lasts up to 100,000 miles before service is required (depending on driving conditions) Replaces entire factory air intake system Easy to install, usually in 90 minutes or less