What you need to know about a FASS Fuel System

FASS stands for Fuel Air Separation System, and it is a combination of a lift pump and filtration system for diesel fuel. The purpose of FASS is to improve diesel fuel mileage and engine performance while extending the life of a diesel injection system. This article will discuss some of the benefits of FASS. Once you better understand FASS, you can make a wise decision when purchasing one for your vehicle.


A FASS Fuel System is designed to improve the performance of diesel pickup trucks, thereby improving lubricity and saving diesel injectors. Its advanced machining technique prevents the reintroduction of air into the fuel and eliminates eddy currents by creating smooth flowing cuts. FASS Titanium Signature Fuel Systems are the only fuel air separation systems with Performance Radius Cuts, while lesser competitors use T-Bone and square 90-degree fittings.

One of the most important benefits of a FASS fuel system is its superior engineered pumps. They have a less than 2% failure rate and are highly reliable. Moreover, they feature many innovative features not available in other fuel systems. If you are interested in upgrading your fuel system, you can contact FASS Diesel Fuel Systems today to learn more about the benefits of FASS products. 


A FASS fuel system combines a diesel fuel lift pump and a filtration system. It is designed to improve fuel mileage, enhance engine performance, and extend the life of diesel injectors. The FASS diesel fuel system is a great way to upgrade your fuel system and give your truck a new lease on life. The FASS system is made in the USA and includes many benefits that you will find beneficial for your truck.

The Titanium Series Diesel Fuel Pumps are the only fass fuel air separation system to incorporate Performance Radius Cuts. These advanced machining processes prevent stagnate fuel pockets within a 90-degree bend. A FASS Titanium Series fuel pump has this unique design unique to the industry. Most lesser competitors use square or T-Bone 90-degree fittings, which restrict flow and increase the risk of air contamination.


FASS fuel systems are becoming popular in the diesel truck market. These systems increase fuel mileage, improve engine performance, and even extend diesel injectors’ life. FASS offers a wide range of fuel systems, including pickup engine kits and universal Class 8 semi pumps. A significant advantage of the FASS fuel system is that it removes contaminants from the fuel, including water, air, and dirt. The cost of a FASS fuel system can range from $800 to $2500.

Diesel engines are notoriously noisy, but FASS fuel systems have mastered making them as quiet as possible. The Signature Series FASS diesel fuel lift pump features FASS Whisper Technology, which drastically reduces engine noise and increases fuel flow rates. As a result, these systems are among the quietest on the market. FASS diesel fuel systems also feature a unique, patented air/vapor removal process.


Before installing the FASS system, you must prepare the tank and the fuel return lines. First, remove any plugs and thread tape the ends of the fittings. Then, install the brass fittings, spacers, and brackets. Be sure to tighten the bolts and torque them properly. Next, connect the return line to the FASS unit. It should be attached to the “E” port of the FASS.

Connect the ADD-A-CIRCUIT 46177 lead into the fuse panel located in the engine compartment. Locate fuse position #F70 (FUEL MTR). The FASS must be installed in the correct location. Install the BHF assembly in the best location. You must prime the system by running the fuel pump for 15 seconds.