A part from the clatter of combustion and the smell of the exhaust, one of the reasons we love diesel trucks is their reputation for reliability. It seems like the harder you work them, the happier they are. And when gasoline engines are giving up the ghost after 100,000 miles, diesel engines are just getting started. But no engine system is infallible, and in the case of many Dodge Cummins models, the Achilles' heel is often the fuel-lift pump.
 Because of the extreme demand...  Because of the extreme demand placed on the injection pump when the lift pump fails, the teeth on the pump shaft can actually begin to strip, as shown here. |  The injection pump is lubricated...  The injection pump is lubricated by diesel fuel under pressure. When flow is diminished because the lift pump can no longer hold its own, scuffing of low-tolerance components like this advance piston can occur. |  The factory Bosch VP44 injection...  The factory Bosch VP44 injection pump (used in '98 1/2-'02 Dodges) is a pretty rugged piece, but when it's trying to pull fuel against a failing (or failed) lift pump, expensive damage can be the result. |
What a Lift Pump Does
Every diesel engine utilizes a high-pressure injection pump, driven by the engine, to deliver fuel under extremely high pressure to the injector nozzles. However, asking the injection pump to simultaneously draw fuel through several feet of line from the fuel tank is too much, so on Dodge and Ford diesels, the injection pump gets a leg up from a fuel-lift pump.
 Here, the transfer-pump ring...  Here, the transfer-pump ring is compared with a quarter for a size comparison. From here, the damage to the ring may not seem like much. |  In the close up, you can see...  In the close up, you can see evidence of severe scuffing and also chatter marks-both of which are caused by an insufficient fuel supply to the injection pump. |  Use the mounting bracket as...  Use the mounting bracket as a template, then mark and drill the 1/4-inch mounting holes in the frame. |
When Lift Pumps Fail
The lift pump on modern diesels is a small, electric unit that draws fuel from the tank and through the filter, delivering it under low pressure (around 7-15 psi, depending on load) to the injection pump. When the lift pump gets old, its performance can suffer, placing added strain on the injection pump. And when the lift pump fails, it can actually kill the injection pump, which means you'll be left stranded wherever you are. It also means you're in for a serious repair bill; a new or rebuilt injection pump, plus labor, can set you back more than $1,000.
 Tap the holes using a 1/4-inch...  Tap the holes using a 1/4-inch national coarse (NC) tap. |  Apply thread locker to the...  Apply thread locker to the threads of the longer studs on the rubber isolators, then screw them into the mounting holes. |  Install the rubber pump mounts...  Install the rubber pump mounts in the bracket, and install the pump-mounting bracket on the framerail. |
Preventive Measures
The good news is you can safeguard against lift-pump failure with a lift-pump kit from BD Diesel Performance. BD has been in the diesel game for 35 years, and its subsidiary company, Valley Fuel Injection, is a certified Bosch, Delphi, Stanadyne, and Zexel calibration and repair lab.
 Install the brass pump fittings...  Install the brass pump fittings to the pump body (no sealer is necessary), and mount the pump to the bracket. |  Install the two pieces of...  Install the two pieces of rubber fuel line with one clamp on each brass fitting and two on the steel lines, as shown. |  The factory electric pump...  The factory electric pump has been removed, and a BD technician is installing the adapter. |
BD and Valley Fuel Injection have developed a line of diesel lift-pump kits to prevent problems before they happen and improve injection-pump life at the same time. Essentially, there are two types of kits-OEM Bypass and Tandem-and which one you use depends on the model of the year truck you own.
With the OEM Bypass kit, the factory engine-mounted lift pump is removed and replaced with a frame-mounted unit. The Tandem kit, as the name implies, is used in tandem with the factory lift pump, whether it's engine-mounted or in-tank.
"The OEM Bypass kit is the perfect replacement for the stock engine-mounted pump, which is no longer available from Dodge," says Blair Parker, BD's vehicle service manager. "In fact, the factory will sell you an in-tank pump to replace it, which requires additional cost in both parts and labor." Parker notes that BD still carries OEM, engine-mounted lift pumps for applicable models and that many auto parts stores do, as well.
 With the pump mounted, it's...  With the pump mounted, it's time for the power supply. Connect the wiring harness to the pump (red to positive, black to negative) and run it to the engine compartment along the driver-side framerail. Attach the harness to a battery positive and negative, and secure the wires with the supplied nylon ties. |  BD manufactures its own custom...  BD manufactures its own custom fitting (included with '03-'04 kits) to make the connection from the fuel line to the fuel bowl once the engine-mounted factory pump is removed. Here, the pump from an '03-'04 Dodge Cummins application is shown alongside the BD adapter. |  Installing the BD lift-pump...  Installing the BD lift-pump kit is a fairly straightforward procedure. The first step is to locate a suitable area on the inside of the driver-side framerail to mount the pump, then cut the factory fuel line where it runs along the framerail (shown, with red cap). Note that fuel on the supply side of the injection pump isn't under more than a few pounds of pressure, so there is little danger in cutting the line. Never disconnect or cut into fuel lines on the delivery side of the injection pump because this fuel can be under several thousand psi of pressure-enough to cause serious injury. |
Pump Prices
"If the pump is still working satisfactorily, the Tandem layout can be used," Parker says. "Our lift pump is also good for use on later models with the factory in-tank pump for higher-power applications, as the in-tank pump is only sufficient for mild upgrades." The Tandem kit part number is 1050226; the OEM Bypass kit for '98 1/2-'99 trucks is 1050230; for '00-'02 it's 1050229; and for '03-'04 trucks it's 1050227. Kits range from $250-$270, depending on the application.