The 2003-2004.5 3rd Gen Cummins originally came equipped with a fuel lift pump mounted in the engine bay. Later Dodge or Cummins, whomever you want to blame, realized this was a bad idea and beginning with the 2005 model years, began installing the pump into the fuel tank's basket assembly, as well as retrofitting trucks once their lift pump failed to this design. Okay, so this was better, but for anyone that either wanted even better than this, or their engine demanded anything more than factory fueling levels, this in-tank pumps made upgrading to an aftermarket lift pump quite the chore. In the past, with an in-tank pump, you had a couple of options to retrieve fuel from the tank. First, you could install what is commonly referred to as a "draw-straw" in which you drill a hole in the top of your tank and install a bulkhead fitting with a tube that goes into your tank. Unfortunately, for many, this resulted in what's known as "1/4 tank issues" where the straw is unable to pull fuel from the tank once fuel levels dipped below 1/4 of a tank. Secondly, you could install a sump where you're required to remove all fuel from your tank and install basically a bowl on the bottom of your tank and fuel is drawn from the lowest point on the tank. While this is great in order to simplify the process and eliminate these 1/4 tank issues, they're troublesome to install, prone to leaking if not sealed properly, and require a hose to run along the bottom of your tank.
Fleece Performance sought to rectify all of these issues created by having an in-tank pump, and they have, with their SureFlo Performance Sending Units! SureFlo performance sending units are designed to work with aftermarket lift pumps and fits directly into your stock sending unit location. It features factory style quick disconnects to adapt your stock fuel lines at the tank, giving you the cleanest installation available, and requiring no cutting or drilling of the tank. SureFlo works by drawing fuel from, and returning fuel to, the bucket assembly at the base of the unit. This ensures you are always drawing fuel into your pump and not drawing air into the fuel system as well as eliminates the dreaded 1/4 tank problems. The SureFlo bucket also incorporates one way check valves to allow fuel to easily flow in at lower levels.
Fleece SureFlo performance sending units are also a great alternative for trucks originally equipped without an in tank pump needing to repair a malfunctioning level sender or if you are simply looking to run your own custom fuel lines directly to the tank.