Fuel Tank Sump Kit for Diesel Truck AirDog FASS - Integrated Return

In this review of the Fuel Tank Sump Kit for Diesel Truck AirDog FASS, the bottom line is simple: this is a practical, no-tank-drop solution for diesel owners who want a clean way to feed and return fuel to inline lift pumps. The kit's single biggest selling point is the built-in fuel return with a stand pipe that separates return fuel and feed, reducing the risk of air entrainment and keeping the pump supply stable without removing the tank. For anyone running AirDog or FASS systems on common diesel platforms, this is a straightforward upgrade that prioritizes reliability and easy installation.

Key Features

• Built-in fuel return: Integrates the return line into the sump so return fuel is routed separately from the feed for more consistent pump supply.
• No tank drop installation: Designed to be installed without removing the fuel tank, saving time and avoiding heavy disassembly.
• Included 3' hole saw: The package includes a 3' hole saw to simplify cutting the tank access opening for the sump.
• Aircraft grade construction: Machined from T6 billet aluminum for durability and corrosion resistance compared with stamped alternatives.
• Compatibility: Works with stock and many aftermarket tanks on Cummins, Duramax, and Powerstroke trucks equipped with AirDog or FASS pumps.
• Fittings and warranty: Ships with 1/2' fittings and carries a 1-year warranty for basic coverage and peace of mind.

Who It's For

This kit is aimed at diesel truck owners who run an AirDog or FASS lift pump and want a reliable in-tank feed and return solution without dropping the tank. It fits well for people comfortable with light metalwork and basic drilling, and for those who value OEM-quality materials like aircraft grade T6 billet aluminum.

It is not ideal for off-road vehicles or applications with low ground clearance where a protruding sump could be damaged, and anyone uncomfortable with drilling into a fuel tank or who cannot ensure the tank is clean of debris should consider professional installation or an alternative mounting approach.

Pros & Cons

Pros

• Easy installation for most users thanks to the included hole saw and no tank removal requirement.
• Solid, high-quality feel and leak resistance from billet T6 aluminum construction and included fittings.
• Effective separation of return and feed reduces aeration and helps the lift pump perform consistently.

Cons

• Not recommended for off-road use or for vehicles with potential ground clearance issues where the sump could be vulnerable.
• Installation requires drilling into the tank and care to remove debris, which may deter some DIYers or require a shop.

Specifications

Our Verdict

The Fuel Tank Sump Kit is a practical choice for diesel owners running AirDog or FASS systems who want a durable, well-made in-tank solution without dropping the tank. Its billet construction, included hole saw, and separate return stand pipe make it good value for those comfortable drilling and performing light installation. Avoid it on low-clearance or heavy off-road trucks where the sump could be exposed.

Frequently Asked Questions

Will this work without removing the fuel tank?
Yes, the kit is designed for no tank drop installation using the supplied hole saw to cut an access opening.

Is the kit compatible with my truck?
It is intended for Cummins, Duramax, and Powerstroke diesel trucks equipped with AirDog or FASS lift pumps; confirm tank fitment before purchasing.

Is off-road use recommended?
No, the manufacturer does not recommend this sump for off-road use or vehicles with potential ground clearance issues.