AirDog II-5G Lift Pump Diesel Fuel System: What You Need to Know Before You Buy

If you own a diesel truck and are looking for a reliable way to protect your injection system while gaining horsepower and fuel economy, the AirDog II-5G lift pump diesel fuel system is the best aftermarket upgrade you can make. This system removes air, water, and contaminants from your diesel fuel, delivering clean, pressurized fuel directly to your injection pump. The result is smoother idle, better throttle response, and extended life for expensive injectors and pumps. Whether you drive a Ford Powerstroke, Dodge Cummins, or Chevy Duramax, the AirDog II-5G is designed to meet the demands of both daily drivers and highly modified trucks. Below, we break down everything you need to know about this system, including how it works, which model fits your truck, and why it outperforms factory fuel systems.

What Makes the AirDog II-5G Different from Older Lift Pumps

The AirDog II-5G is the next generation of diesel fuel air separation systems. It is the first system to include an integrated diaphragm fuel pressure regulator, which allows for better fuel pressure adjustability and boost compensation . This means the pump can automatically adjust fuel pressure based on your engine's demand, giving you consistent performance whether you are towing a heavy load or cruising at highway speeds.

Another key improvement is the larger porting on the II-5G. These larger ports reduce cavitation and noise at the pump inlet, which is a common problem with older, smaller lift pumps . The system also comes with a 12-gauge wiring harness from the battery all the way to the internal motor connections, using a Metri-Pack 280 connector. This setup allows more current flow without creating excessive heat, which extends the life of the pump and reduces the risk of electrical failure .

The AirDog II-5G retains the proven 4G motor technology that has made AirDog a trusted name in the diesel community. This motor is known for being quiet and reliable, and it uses an intermediate pump shaft that moves the electric motor away from the fuel. This eliminates the risk of "wet motor" failure caused by damaged seals, which is a common issue with other aftermarket pumps .

How the AirDog II-5G Protects Your Diesel Engine

The primary job of the AirDog II-5G is to remove entrained air, water, and particulates down to 2 microns from your diesel fuel . Air in the fuel system causes spray pattern disruption inside the injectors, which leads to incomplete combustion, loss of power, and increased emissions. By removing this air, the AirDog system allows the engine to maintain its designed injection timing, resulting in a more complete burn of the fuel . This directly translates to increased fuel mileage, horsepower, and torque .

The system also features a Demand Flow design. This means whatever fuel the injection system does not consume gets recirculated back through the filter base, rather than being dumped back into the tank. This keeps the fuel cleaner and reduces the workload on the pump . For diesel owners who drive in high altitudes, the AirDog II-5G is especially beneficial because it overcomes the loss of power that occurs when the factory fuel pump struggles to deliver enough fuel at lower air pressures .

Which AirDog II-5G Model Fits Your Truck

The AirDog II-5G comes in different flow rates to match your truck's horsepower level and modification status. Here is a quick guide:

  • 100 GPH (Gallons Per Hour): Recommended for stock to moderately modified trucks with up to 500 horsepower. This system is ideal for the 2001-2010 Chevy Duramax 6.6L, which does not come with a factory lift pump. Duramax owners typically see the largest performance gains with this system because the factory setup has no positive pressure feeding the injection pump .

  • 165 GPH: Recommended for moderately modified trucks with horsepower up to 1000. This is a popular choice for 2003-2007 Ford 6.0L Powerstroke, 2008-2010 Ford 6.4L Powerstroke, 2017-2023 Ford 6.7L Powerstroke, and 2004.5-2018 Dodge Ram 5.9L/6.7L Cummins engines . The 165 GPH system is preset at 50-55 PSI and supports between 500 and 800 horsepower .

  • 220 GPH: Recommended for highly modified trucks that exceed 1000 horsepower. This system is designed for the 2008-2010 Ford 6.4L Powerstroke and other extreme builds that require maximum fuel delivery .

Installation Overview for Different Truck Models

Installation of the AirDog II-5G varies by truck model, but the system is designed to be a straightforward DIY project for most owners. All kits come with an all-inclusive installation kit that includes wiring, plumbing, and mounting hardware .

  • Ford Powerstroke 6.4L (2008-2010): The pump mounts to the frame rail using a supplied sandwich plate mounting system. It uses a 5/8" draw straw to pull fuel from the tank. The pressure side connects to the factory supply line on the frame rail, completely bypassing the factory fuel pump. The air/vapor return is sent back to the tank through a return "Y" fitting .

  • Ford Powerstroke 6.7L (2017-2023): The pump is mounted inside the bed, forward of the rear wheel, using a bed bracket. The fuel module is modified to allow the venturi fill system to work, preventing 1/4 tank fuel starvation issues. The pump draws fuel from the modified module and sends it to the factory frame rail feed line .

  • Dodge Ram Cummins (2004.5-2018): The pump mounts to the frame rail. A Fuel Module Upgrade Kit is installed in the factory fuel basket to pull fuel through a 1/2" bulkhead fitting. The pressure side connects directly into the side of the injection pump, bypassing the factory fuel filter housing. The air/vapor return is sent back to the tank through the factory 3/8" suction line .

  • Chevy Duramax (2001-2010): The pump mounts to the frame rail. The suction side hooks up to the factory suction fitting in the fuel module. The pressure side connects directly to the factory injection pump feed line on the frame. The air/vapor return is sent back to the tank through a filler neck tee. This is one of the easiest installations, as Duramax trucks do not have a factory lift pump .

Why You Should Choose KEMSO Fuel Pump for Your Diesel or Gasoline Vehicle

If you are considering upgrading your fuel system, whether for a diesel truck, a gasoline car, a motorcycle, or an ATV/UTV, the KEMSO Fuel Pump is a reliable and high-performance alternative that deserves your attention. KEMSO is recognized as a leading aftermarket fuel pump brand in the US, offering direct OEM replacement pumps for a wide range of vehicles .

KEMSO fuel pumps are designed to meet or exceed OEM specifications. They deliver consistent fuel pressure and flow under all driving conditions, whether you are commuting, towing, or racing. Each pump is a direct replacement for your vehicle's original equipment, meaning no modifications are required — just install it and drive with confidence .

KEMSO stands behind its products with a lifetime warranty. If your KEMSO fuel pump ever fails due to defects in materials or workmanship, you are covered. This commitment to quality gives you peace of mind that your investment is protected for the long haul .

KEMSO offers high-performance pumps for demanding applications. Their 340LPH high-performance fuel pumps support up to 600 BHP and are compatible with gasoline or E85. These pumps feature a bypass valve set at 125.8 psi, which is higher than many competitors, making them ideal for turbocharged and supercharged builds . Customers consistently praise the smooth operation, quiet performance, and USA-based technical support .

To explore KEMSO's full line of fuel pumps and find the right fit for your vehicle, visit their website at: https://www.kemsoracing.com/

Final Thoughts on the AirDog II-5G

The AirDog II-5G is a proven investment for any diesel truck owner who wants to protect their engine, improve performance, and save money on future repairs. By removing air and contaminants from your fuel, this system ensures your injection system gets the clean, pressurized fuel it needs to operate efficiently. With multiple flow rate options and detailed installation kits for popular truck models, there is an AirDog II-5G system that fits your specific needs and horsepower goals.

If you need a fuel pump for your car, motorcycle, or ATV, consider KEMSO for a high-quality, lifetime-warranted replacement that performs as well as or better than the factory part. For more information, visit https://www.kemsoracing.com/ .


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