Well, as a 2nd gen owner, i never knew 3rd gens had any issues with lift pumps until i cruised on your forums. Are they as common as 2nd gen problems???? Is the cp3 any better than the VP or just set up for common rail?

What brand are the stock lift pumps you run and where are they located.


I have a friend who has a 2005 and wants to do the walbro kit. Will it be a setup like what i run on my 02, or does the 3rd gen walbro go in the tank???


Thanks fellas.

 

The 03-04.5 trucks had/have some issues with the filter mounted lift pump. Starting in 2005 all the pumps went to an "intank" pump that seems to have a better track record. All year Dodge Cummins trucks (including 2nd gens) now have the "intank" pump put in if the dealer does a "fix" for a dead pump.


The Cp3 injection pumps seem to be doing great. If you keep it fed with fuel, you rarely hear about a failure here. I know the VP-44s are not as reliable.

The walbro is mounted inline on the frame rail usually. Not in tank. If your buddy wants one for his 05 it will be a little bit more work and will have to drop the tank to remove the stocker. But that will be an excellent time to do the fuel tank vent mod and add an extra 5 gallons of capacity to the tank. If your friend wants to run his truck stock...I wouldn't bother messing with the Walbro. If he plans to bomb it, then the Walbro is an excellent choice. So is FASS.

 

From what I've read (correct me if I'm wrong), a VP44 will run with a weak or failed lift pump so you may not know there's a problem until the VP44 gets damaged from lack of head pressure. The CP3 trucks apparently quit running when the lift pump doesn't provide pressure, so at least the injection pump doesn't get ruined when the lift pump dies...

 

The CP3 Inj Pump has a built-in gearotor-style lift pump, driven by the pump shaft - it will develop 20" vacuum at higer rpm, and is designed to pull fuel from the tank thru a filter.

The '03-'04 trucks have an additional Carter-style rotary lift pump mounted on the fuel manager head - those are not flow-thru when fail type, so the CP3 cannot pull fuel from the tank as the electric pump fails - this will leave you on the side of the road, even tho the CP3 could get you home

The '05-up trucks have an in-tank electric lift pump that runs at a constant 9psi - it flashes toward 30psi at key-on, then settles back to 9psi as the CP3 bypass begins to function - it is a vane-type flow-thru when fail pump, designed to run in Diesel fuel, so the CP3 can draw fuel from the tank if the electric pump fails - this setup will not leave you stranded on the road, dead.

DCX has a conversion kit to upgrade the '03-'04 systems

If you go with an aftermarket type lift pump, make sure it is flow-thru when failed type, so the CP3 can do it's job.

The

 

I just installed the Walbro, fuel tank vent, and big line kit on my truck. If you decide to help your friend with any of this just make sure the vent location is picked very carefully as I only had about a 1/4 inch of clearance once it was installed.(my fault as I didn't double check location and follow instructions by marking crossmembers on the tank)

The job is pretty easy if you have a garage or shop to work in. I did mine in the rain in my mudhole driveway. It started out just fine but then decided to dump about an inch of rain after I had cut the fuel line. I didn't have any choice but to get it finished as I had to get the truck drivable.

Check that all fittings are the correct size as I had one that wasn't and had to run to the local auto parts to get the right one. Looked like someone dropped a metric into the parts bin so the fitting would not fit. Other than that it was a simple job.

If your friend decides to do it make sure he joins up here and gets all the online help he can use. Also use the DTR Store for best pricing.

 

An in tank pump is like any other car on the road, and only have to push, not suck and push like a rail mounted pump.I'd
say it's the best configuration to have, but a pain in the butt to change out.

 

The Bosch CP3 injection pump that is used on the Dodge Cummins ISB is the same pump that is used on the GM D-Max 6.6L V8. In fact, the D-Max does not use a lift pump in their system; the Bosch unit is designed to pull pump directly from the tank. As stated before, the CP3 will pull 20" of vacuum.

Where Dodge really screwed up is when they mounted their lift pump on the fuel filter to supply the VP44 injection pump. Carter told them that the lift pump was designed to "push" fuel and not "pull" fuel; that the pump mounted so far from the fuel tank would fail in time. They were right, it cost a lot of people a lot of money to replace failed VP44s that were out of warrranty. And how does Dodge fix the problem? They put the lift pump in the fuel tank to push the fuel to the injection pump. This is a classic case of "closing the barn door after the horses are gone".

Here is a true story about a friend of mine who owns a '99 Dodge Ram 3500 DRW w/CTD 5.9L:

It's a "trailer puller". He "winters" in Arizona each year and pulls his very large 5th wheel trailer back and forth to Washington. On one trip he lost power on a long grade. He stoppped at the local Dodge dealer and they replaced the failed lift pump that was mounted in the stock location on the fuel filter. Problem solved, right? Down the road he went; the engine ran well. The dealer didn't tell him that the VP44 injection pump had incurred damage because of low fuel supply pressure (maybe they didn't know or realize what a failed lift pump could do). The following year, again on the road from Arizona, the truck just stopped running. He was towed to the closest dealership where they diagnosed a failed VP44 injection pump. And they would not warranty the installation of a new one unless he agreed to them installing a new lift pump in the fuel tank, which was then Dodge's answer to the whole lift pump problem. Of course, he agreed, opened his wallet and the story ends; he is about $3K short in his bank account with all the repairs. Oh, the truck was out of warranty, so he got no help from Dodge. Even though they knew from the start that the stock lift pump was bound to fail.

I'd be willing to bet there are many stories similar to this out there.