Shop below for FASS fuel air separation systems for your GM Duramax Diesel. The FASS Fuel Systems product line for GM Duramax diesel pickups is the best selling aftermarket diesel fuel pump and Filtration Systems (Titanium Series) on the market today. FASS Fuel Systems are designed to eliminate air and vapor trapped in diesel fuel. When air and vapor are eliminated and replaced with pure fuel we are able to provide your diesel engine with the cleanest burning fuel possible. Please take a look at our FASS products and if you have any question please feel free to give us a call.