Replace your old and dirty air filter with a Drop-In Air Filter for your 2018-2021 Ford 3.0L Powerstroke. An air filter is a crucial component for your engine and its purpose is to keep harmful airborne dust and debris out of your engine. A drop-in air filter is named after the simple installation procedure as it simply drops into the factory airbox in most applications. Most factory-style drop-in air filters are made with a paper filter media, and aftermarket performance air filters generally use a cotton-gauze media that requires filter oil, or a synthetic dry media. Replace the factory air filter on your vehicle with a quality drop-in air filter from S&B Filters, AFE, K&N Engineering, and others at XDP.