2005-09 Mustang K&N K&N Air Filter 4.0/4.6 by K&N

K&N - The World's Best Air Filter
K&N’s lifetime replacement air filters are designed to increase horsepower and acceleration while providing excellent filtration. K&N air filters are custom designed to fit into your Mustang's factory air box. Their drop-in design means adding performance is simple. Simply remove the disposable air filter from your Mustang and replace it with a K&N; there is NEVER any cutting or fitting required. K&N stock replacement air filters for Ford Mustangs are covered by the famous K&N Million-Mile Limited Warranty and will be THE LAST AIR FILTER YOUR MUSTANG WILL EVER NEED.

K&N's Million Mile Limited Warranty
K&N replacement air filters are built so well, that they warranty them for 1,000,000 miles! This means you can count on them to continue delivering engine protection and high airflow for the life of your Mustang.

Why Choose K&N?

• Engineered Power : State-of-the-art air filter media is designed to increase horsepower and acceleration as well as improve overall engine performance
• Rugged Construction: K&N Air Filters are manufactured with durable, premium materials and state-of-the-art construction methods to last a lifetime
• 4 Layers Of Protection: Multiple layers of premium cotton gauze treated with a specially-designed tacking agent work together to create an intricate mesh of engine filter media that is designed to block and trap harmful contaminants
• Clean Once Every 5 Years: Engine air filter only needs cleaning every 75,000 miles under normal highway driving conditions (5 years based on the average miles driven per year of 15,000 miles) We suggest checking every oil change for level of contamination. 
• Saves You Money: A K&N washable, reusable air filter will save you up to $125 vs. purchasing multiple disposable filters (compared to MSRP in USD of corresponding OE filters for 200,000 miles of highway driving)
• Ultimate Longevity: No-hassle lifetime limited warranty on stock replacement K&N air filters- limitations apply
• Easy Install: K&N Air Filters are pre-oiled and ready to drop into your factory air box- they are one of the easiest and most cost-effective vehicle upgrades for quick performance gains
• Reduces Waste: Over 200 million disposable air filters and their packaging waste wind up in landfills each year- reusable filters help reduce waste in our landfills

K&N Warranty - Click Here