PureFlow AirDog II-5G 98.5-04 Dodge 24V 5.9L Cummins (w/Pump) DF-100-5G Fuel Air Separation System
The 1998.5 to 2004 Dodge Ram 5.9L 24-valve Cummins is hard on lift pumps, and the injection pump pays for it. On the 1998.5-2002 trucks a VP44 that runs short of fuel or on aerated fuel fails early, and the 2003-2004 common rail CP3 does not like it either. The PureFlow AirDog II-5G DF-100-5G (A7SPBD354) is a frame-mounted 100 GPH lift pump with built-in air and vapor separation, filtration and an adjustable regulator. This version is for trucks that have an in-tank fuel pump in the factory fuel basket.
The AirDog draws fuel from the tank, passes it through a water separator, pressurizes it with a gerotor pump and sends it through a 2 micron fuel filter to the injection pump. A diaphragm regulator holds the pressure and recirculates the extra fuel, and the air and vapor it pulls out of the fuel are sent back to the tank. On this kit a Fuel Module Upgrade Kit goes into the factory fuel basket so the AirDog pulls through a factory-style 1/2 inch bulkhead fitting and bypasses the old in-tank pump. The modified module also lets the air and vapor return go back through the factory 3/8 inch suction line. The pressure side goes straight to the inlet on the VP44 or CP3, so the factory filter housing is bypassed. AirDog sizes the DF-100 for stock fuel trucks.
Put a gauge on the supply side at the injection pump and watch it at idle and at full load. Pressure that falls away under load means the supply system cannot keep up. Change the filter and check again. Also rule out the transmission: a 47RE or 48RE that slips, or a converter that will not lock, can feel like low power. Our 47RE Ram 2500 Cummins guide covers the 1998.5-2002 trucks and the 48RE Cummins transmission problems guide covers 2003-2004.
AirDog lists A7SPBD354 for 1998.5-2004 Dodge Ram trucks with the 5.9L 24-valve Cummins: the VP44 trucks from 1998.5 to 2002 and the early CP3 trucks from 2003 to 2004. It is the version for trucks WITH an in-tank fuel pump. Trucks that still use only the engine-mounted lift pump need the DF-100-5G version built for trucks without the in-tank pump. Pull the tank sender or check your service history before ordering, and if you are not sure which you have, send us the year and VIN. Browse more parts in the engine and fuel parts category and on the 47RE parts page.
On a 2003-2004 truck with a tired CP3, pair this with a BD stock exchange CP3. Towing heavy? Add a braided cooler line kit for the automatic.
| Brand | AirDog |
| Part number | A7SPBD354 |
| Fits | PureFlow AirDog II-5G 98.5-04 Dodge 24V 5.9L Cummins (w/Pump) DF-100-5G Fuel Air Separation System |
| Type | Fuel Air Separators |
| Condition | New |
| Ships | Same business day (in stock), from the USA |
| Warranty | 1-year |
A7SPBD354 is for trucks that have an in-tank fuel pump in the factory fuel basket. It comes with a Fuel Module Upgrade Kit that lets the AirDog draw through that basket and bypass the in-tank pump. Trucks without an in-tank pump use a separate DF-100-5G kit.
AirDog sizes the DF-100 for stock fuel trucks. If you have added large injectors or a stroker pump, a higher flow AirDog model is the better match.
The regulator is preset at 15-17 psi from the factory. It can be adjusted with the truck running and a gauge connected; AirDog warns that running above 75 psi shortens pump life.
No. AirDog says removal is not necessary. On 2003-2004 CP3 trucks, removing it requires a separate filter bypass because the engine return runs through the housing.
AirDog lists typical fuel filter life at 15,000-20,000 miles depending on fuel quality, with the water separator replaced every other filter change and drained about every three months.
