2003-2004 Dodge 5.9L Cummins Fuel Sumps

Fuel sumps on the 2003-2004 Ram 5.9L Cummins

From the factory, the 2003-2004 5.9L Cummins pulls fuel out of the tank with an electric lift pump bolted to the engine on the fuel-filter canister. That pump makes only about 10 psi and has to pull fuel the full length of the truck. Frame-mounted pump and filter systems turn that around. The pump sits on the frame rail and pushes fuel forward, so it needs its own pickup in the tank. Kits use either a draw straw or a sump for that pickup. This page is the sump side.

Why owners add a sump

A sump is not a repair part by itself. It shows up when an owner moves to a frame-mounted lift pump, which is the standard answer to a factory pump with an 80,000-120,000-mile life that TDR says may not be adequate for much more than 60-70 hp over stock. Draw straws have their own catch on these trucks: the stock in-tank sender and its basket float can hang up on a poorly placed straw. Some owners also leave the engine-mounted pump in place as a spare after the new system goes in, which gives the truck a second fuel path if the primary pump ever quits.

One-hole or return-style

The main difference between the sumps here is the return. A one-hole sump gives your pump system a single pickup. A return-style sump adds a fuel return, so the system's return line can come back into the tank at the sump. Which you need depends on how your lift pump kit routes its return, so read the kit's install instructions before you choose. Also check whether your kit already ships with a draw straw; if it does, you may not need a separate sump.

What we carry

XDP MFG offers the XD182 Fuel Tank Sump in a one-hole design and the XD243, a one-hole design with a fuel return. BD Diesel makes the 1050330 Flow-Max Fuel Tank Sump, and G&R Diesel builds the GRD00153 Bottom Sump with an integrated return. Every sump on this page is a pickup for a pump system, not a pump.

Fitment notes

Installing a sump means getting at the tank: either drop it or lift the bed. The bed comes off with six 18 mm bolts; put Loctite on them going back in. Fuel parts on this truck are year-specific. 2003-2004 trucks have the lift pump on the engine and 2005-2007 trucks have it in the tank, and a 2003-2004 truck that already got the Mopar in-tank relocation kit needs 2005-style parts. Mopar also documents both 34-gallon and 35-gallon tanks across these trucks' wheelbase and bed combinations, so confirm the listing covers yours. Verify by VIN if you're unsure.

Frequently asked questions

Do I need a sump to run a frame-mounted lift pump on my 2003-2004 Cummins?

The pump needs a pickup in the tank, and a sump or a draw straw is how those systems get one. Check what your kit includes first. Either way, the kit replaces the stock suction line with larger supply hose.

Can I keep my factory lift pump after installing a sump?

Yes. Some owners leave the engine-mounted pump in place as a spare, which gives the truck a second path for fuel if the new pump fails. TDR used that setup on its own project truck.

Do I have to drop the tank to install a sump?

Either the tank comes down or the bed comes off. The bed is held by six 18 mm bolts, and they get Loctite on reinstall. If you'd rather not tackle it, we do this work in our Wildwood, FL bays.

Should I get a sump with a fuel return?

It depends on your lift pump system. If the kit routes its return back to the tank, a return-style sump like the XDP XD243 or the G&R Diesel GRD00153 gives that line a place to go. If not, a one-hole sump like the XD182 covers the pickup; check the BD Flow-Max listing for its port layout.

Not sure what fits? Call the shop at the number in the header, or use the fitment checker on any product page. We install everything we sell.