The lift pump is used on many diesel engines to transfer fuel from the fuel tank to the fuel injection pump. The lift pump runs at all times when the key is on and many OEM lift pumps have a short life span due to this duty cycle. Without the proper supply of fuel, your injection pump is unable to supply the proper pressure and or lubrication required. When the lift pump fails, the injection pump will continue to draw fuel through the lift pump under vacuum. Normally you can tell little or no difference in the engine operation when this happens. The injection pump will eventually be unable to achieve the fuel demand from the engine ECM, causing the engine to derate and feel extremely underpowered. At this time, the injection pump will either need to be rebuilt or replaced.
These FASS Dura-Max Flow Enhancer pusher pumps were designed after the FASS DDRP series lift pumps. and is now available for the GM Duramax. GM trucks equipped with the 6.6L Duramax do not have a stock lift pump which forces the injection pump to "pull" the fuel all the way from the tank, creating a vacuum and constantly introduces more air and vapor into your fuel. The Dura-Max Flow Enhancer creates a positive flow of fuel, "pushing" it to your injection pump, eliminating vacuum and drastically reducing air and vapor in your fuel.
NOTE: Only The AirDog FRRP-100 and FRRP-150 Dodge Diesel Lift Pumps are capable of supporting a 5.9L Cummins engine with increased power levels.