If you are doing a Dodge to Dodge conversion, just swap the sensors and alternator from the 24 valve to the 12. Your cruise control will not work though. It will require some rewiring, just don't cut sensor wires. Also the Tachometer will have to be redesigned, as the pickup sensor placement is different for the two engines.

Conversions are never a good idea if you depend on the truck and need it. There are ALWAYS unknowns and issues that crop up and drive the initial cost and loss of use up.

The VP is more reliable than what you are seeing. There has to be something that is contributing to that many failures. What is failing on your specific pumps? Electronics or mechanical?

Any fueling mods, boxes, injectors, etc?


Are you running a FASS\AirDog\other lift pump system?


Frankly, if you want a reliable truck a stock pump with a FASS is about as cheap, easy, and reliable as they come.

I've always fought this P-Pump conversion stuff because it always just seemed like a waste of a good 24V and figured if you were gonna do it then just change engines to the 12V and be done with it.

The truck has a Smarty/Drag Comp stack on it with a belt driven mechanical lift pump, but rarely play much. This truck has never seen EGT's over 1100 degrees in it's lifetime if that tells ya anything about how I drive. I built this thing to pull trailers, not go fast. The Comp was just a toy that I turn off when i hitch up heavy.

I wish I knew why I'm havin these failures cause I know I shouldn't be.

What year is the truck? SO or HO pumps?

You might be able to convert to a 12V simce those trucks did have them at one time. Be interesting to see how integrated the VP44 controls were to all the chasiss pieces.

Is it possible just dropping in a 12V would consist of motor and a few harnesses?

It's a 99 SO truck. I was hopin somebody here could tell us what all the 12V motor switch would take cause we have the one available if we want it. I just don't want to get half way into this and get bit by unexpected expenses and problems.

Actually, I was doing a little research and that will work relatively easily into a 99.

The easy way is to get a 98 12V harness and a front damper with a tone ring and your golden for the electrics. The 98-00 trucks have a crank and cam sensor and all you need is the crank sensor for the tach. The cam sensor is used only for the IP and the 98 harness would remove that.

The 01-02 only had a cam sensor to run everything so you had to use the relocation bracket and a 24v cam gear for the p-pump conversion to get the tach to work. You can make the 24V harness work with some fooling around but you have to remove the CEL bulb as it won't like the absence of the cam sensor and pump connection.

What I have found reccomends getting a 98 12V harness if you can and selling the 24V harness and motor to offset the cost of th enew harness. The other thing that is not clear is exactly when you need to worry about sensors being metric and SAE. You may have to get the 98 sensors to thread into the block or adapt if they need different voltages, but, some have said if its a 99 there isn't a problem.

Do you have an auto or manual? Auto will take some more work as you will need a TPS to replace the APPS signal for trans control.

Its a NV4500 truck.

Will a dampener off a 1995 engine work?

That simplifies things, no TPS to worry about.

I **think** you will need the tone ring off the 24V on the damper or get a 98 damper. Still trying to get some answers on that.

If somebody on here has a 98 12V or you know one someone, could look at the damper and see if it has a tone ring instead of the older notch in the damper setup?

I guess we will have to look at this at another time (in a year or so when this one fails ) as another VP44 has been ordered