CTS Turbo air filters are re-usable DRY element filters and cleaning them is straight forward and easy. Examine your air filter for dirt every 4-9k miles. For optimal engine performance, we recommend cleaning the filter every 20-30k miles, or as required. For cleaning a CTS Turbo dry filter, the best way is to follow these basic steps: STEP 1 Put the air filter into the soapy (we suggest using a alkaline based soap like DAWN, do not use a lot of soap – less is more in this situation) water mixture and let it sit for 5 to 10 minutes. STEP 2 Gently move the filter around in the bucket to loosen any debris. Assess the filter for any large debris lodged and remove accordingly, followed by rinsing with water. DO NOT use a pressure washer or jet option on your hose nozzle. RINSE ALL THE DETERGENT OFF! STEP 3 Shake excess water out and let the filter AIR DRY COMPLETELY.  DO NOT use compressed air as too much pressure will damage the cotton mesh. Washing the filters with water can result in wavy filter pleats, which is normal. OR you may use any filter cleaning kits (AFE Restore kit for Dry filters or equivalent) Follow the instructions provided with the cleaning kit.