TowRig.com - Diesel Discussion and Tow Tech

I'd like to know what the 12v uses for electronics and what not on a '94.

I'm not talking an engine ECM, but other stuff like if there is any kind of "electrical" that controls input for low boost fueling or even what the truck itself uses for it's guages as far as warning lights inside the cab.

Is the tach mechanically driven or is it electrical?

What controls torque converter clutch lockup on these trucks?

Reason why I am asking is I am going to do a Cummins conversion if I can get an engine in mind for the right price and I want to know how much electrical that will be needed to incorporate into the recieving vehicle.

As I understand it the only electrical on a 12v would be for guages and such, although there must be something more than that. Ive heard they are the easiest to swap and always wanted to do that to my old Chevy. A guy in my town swapped a 24v into a Ford and said that surprisingly there wasnt much wiring to that either.

The computer on a Dodge 12 valve does tell the converter when to lock up, the cruise control, speedo, and when to fire up the grid heater.

So how difficult would it be to incorporate that computer into the recieving vehicle?

This is why I told you you will want the whole truck. Basically, when you move the computer over you should have most everything. For cruise control to work and the converter lock up correctly you will have to get a speed signal to the computer. I think your chevy has a mechanical speedo, right?


Basically you will need to mate the wiring for the ignition/run/start and the A/C clutch (if you are going to use it) and such. For the gauges, there are many options there. Either take the original sensors from the old motor and adapt them to work with the new motor (easy) or just replace the gauges with aftermarket units like autometer.