How often should I clean and re-oil my K&N filter?

Under normal street driving conditions, K&N recommends cleaning and re-oiling your filter every 50,000 miles. If you drive in dusty conditions, you will need to service your filter more often.

Do I need to buy special oil to treat the filter?

Yes, K&N air filter oil is specially formulated to work with the cotton filter media. Standard motor oil will clog the filter.

What is the warranty on K&N filters?

K&N warrants its air filters to be free from defects in material and workmanship for 10 years or 1,000,000 miles. Some exclusions apply, such as damage from misuse or improper cleaning.

K&N E-3640 Universal Round Air Filter

Name: K&N Universal Round Air Filter 9in OD / 7-1/2in ID / 4in Height
Brand: K&N
SKU: k-n-engineering-k-n-universal-round-air-filter-9in-od-7-1-2in-id-4in-height-t14-478763
Price: 72.01 USD
Availability: InStock

K&N Universal Round Air Filter 9in OD / 7-1/2in ID / 4in Height

$72.01

Only 1 left in stock

Washable and reusable air filter improves airflow and traps contaminants. Expect increased horsepower.

Key Features

Washable — clean and re-oil for extended use
Reusable — lasts the life of your vehicle
High-flow design — improved airflow over paper filters

⚠️ CA WARNING: This product can expose you to chemicals known to the State of California to cause cancer and/or birth defects or other reproductive harm. Learn more

Secure CheckoutFast Shipping631-982-0042

Product Details

K&N washable, reusable High-Flow Air Filters feature a state-of-the-art design of layered, oiled cotton media engineered to improve airflow and capture contaminants, and are designed to provide an increase in horsepower. Each performance air filter is reusable, engineered to last for the entire lifespan of your vehicle, and backed by K&N's 10-Year/Million Mile Limited Warranty. K&N drop-in replacement filters are designed to install easily into your factory air box. Upgrade today and start enjoying superior airflow and superior performance from K&N's most popular product!K&N washable, reusable High-Flow Air Filters feature a state-of-the-art design of layered, oiled cotton media engineered to improve airflow and capture contaminants, and are designed to provide an increase in horsepower. Each performance air filter is reusable, engineered to last for the entire lifespan of your vehicle, and backed by K&N's No-Hassle Lifetime Limited Warranty. K&N drop-in replacement filters are designed to install easily into your factory air box. Upgrade today and start enjoying superior airflow and superior performance from K&N's most popular product!