Pre-Filters help to prevent sand, mud, and dirt, from contaminating the air filter in your 2018-2021 Ford 3.0L Powerstroke. Finding the right pre-filter for your intake can be done by matching up filter dimensions or by using the corresponding filter part number. Purchase pre-filters from AFE, K&N Engineering, S&B, and many others at XDP! Pre-filters are manufactured from a breathable material that lets air through while blocking large debris and contaminants. A pre-filter provides your vehicles engine, air intake system, and air filter with the protection it needs from large airborne contaminants while also helping to extend cleaning intervals.