Replace Part Number: K37-1012, K37-1029, K37-1011, K371012 K371029, K371011, FS20172. For Peterbilt - 365 367 389 520 567 579 X12 X15 2013-2021. For Peterbilt - 320 X12 2017-2019. Function: Effectively removes dust, pollutants or impurities from the fuel to avoid engine inhalation of contaminants, reduce engine wear and improve engine performance.
