2001 24 valve into a 1998 12 valve?

[Mark Nixon]

What I have is a 1998 12 valve, 2WD C&C 3500 with a 5 speed and an ailing engine.
I also have a 2001 24 valve, 4WD QC 3500 with a 24 valve and a 6 speed, with a very, very rotten body.

Now, I know physically swapping the engine and trannies is easy enough, but, and here's the REAL question:

Will the ECM, PCM and harness from the 2001 play nice with the 1998 fuse box and dash harness, or will all of that have to be swapped out as well?

Mark.

 

[Ol Blue]

Early 01 or late?
Might consider getting fuel lines and putting the fuel system and sensors from the 12V onto the 24V to keep all the 12V gauges and cruise control happy.

 

[Tate]

While this is far from concrete proof, all the wiring schematics I have used from the '01 FSM have matched to both of my '98 trucks. The gauge clusters can be swapped between years, so those should play nicely anyway. Fuse boxes are the same, should be able to disconnect the wiring harnesses at the fuse box and in the upper corner of the engine bay by the hood hinge of one truck to hook the engine up to the other.

 

[Mark Nixon]

I'm wanting to make the 1998 into a 4wd (has a "beam" front axle, now) with the 6 speed.
Since the 12 valve is basically a dead dog and the 24 valve runs fine, I was hoping to just dump the 24 valve in there with the 6 speed and go on my merry way.

Then again, it has crossed my mind to just part them both out and just put the one in the pics together.

Mark.

 

[BigPapa]

My suggestion would be to P-pump it and be done.

 

[5150ram]

I did the exact opposite, it's been a while. I used a 98 12v engine harness and cluster in a 2001. If I remember correctly it wasn't just a simple plug and play. I had to add a few wires in the fuse box and the strangest part was the high beam indicator was reversed.

 

[yankneck696]

Even with 98.5-00 swapping with 01-02, you need the entire engine harness, ECM, PCM, power center & sometimes the gauge cluster & timer module (If you have factory security.
Now, that said, being a die hard VP44 fan, I would suggest the 24 valve engine with the P pump conversion. It may cost more, but if you have time to scrounge parts, you can do it pretty cheap. Already having the 12V for the P pump & the front gearcase cuts the price way down. I THINK all that is left is repopped injectors & conversion lines. You will also have to go with an electric fuel pump, as the 34V cam does not have a FP lobe (Some aftermarkets might).

Ed