98' 12v Engine Plug-N-Play for a 24v Body?

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AMS247

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I have a 98' 12v QCLB currently and would really like to have the same exact thing only a short bed.

If I were to buy a 24v truck, QCSB; would I be able to swap the engine, and wire harness from both trucks and have everything be plug-n-play?

If I can just do that, then put the 24v in the QCLB I currently have and sell that I think would be much easier than shortening the frame, or easier than finding a QCSB 12v' that is still a virgin like my current truck.

I am mainly curious as to whether the 12v engine harness will plug into the firewall plug the same.
 
I think it would be easier to shorten your current truck. Much less work involved. I'd imagine you'd be able to trade your long box for a short box no problem.

Swapping the motors I'd imagine you'd have to change out all of the engine bay wiring and most likely the dash wiring, as well.
 
I would shorten the frame it's not all that bad to do, and would be a heck of a lot easier then swapping all that stuff around.
 
I wouldn't think you'd have to change the dash wiring harness either since the 98' 12v had the same interior dash and cluster as the 24v did.

I have been thinking about just shortening the frame, but if the engine just swapped over, I thought that would save some time. This truck is my DD, and my only vehichle. From the research I've found on shortening the frame it seems it takes most people a couple days, a new drive shaft (or one from a short bed truck), modifying the fuel tank because of the top hump that then would have to clear the cab (or one from a short bed truck), wiring harness can just be tucked up away, shortening brake lines and fuel lines should be somewhat easy, and finally shortening the e-brake cable.

Leveling the back half of the frame seems simple, just time consuming and making the welds strong enough and supportive so when towing you don't get ripped apart. Obviously a short bed is mandatory as well.

If I can find the same thing I have now, a 98' 12v 4x4 virgin motor with around 200k or less on the body but only a QCSB, I'd just buy that and sell my truck, but that's going to be a hard find. I see nice 24v's all the time, so I figured if I can attain a 24v QCSB and pull the motor, I'd be able to pull my 12v and install with wiring in a time period of a long day. That is, if the 98' 12v wiring harness connected to the cab without a problem.

I don't see why Dodge would change that plug if they don't have to, but it is a different motor after all.
 
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I figured more than just the engine bay wiring would have to be changed out because the PCM maybe different. You never know what is different and the same. Just because it is the same interior between a 98 and 02 doesn't mean the PCMs are programmed the same or wired the same. I hate wiring so I would try to avoid it as much as possible.

Shortening the fame, in my opinion can be done in a weekend. Just gather all of your parts before hand. Have new brake lines on hand, have a new fuel tank on hand, have new a new drive shaft made up before hand. The rest of the stuff is not imperative to have done before you drive it. IMHO, it would be easier and less of a headache down the road if you shortened the frame.

And if your concerned about welds being strong enough, weld it and plate it...
 
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The engine harness and underhood harness with fuse box are different between 98 12v and 98 24v
The fastest and less problem would be cut the frame.
 
The dash wiring is the same you need to swap the wiring from the firewall out and the pcm. That's assuming they are both a manual transmission. I have done the swap on a 98 truck it works fine.
 
Well thank you for clearing that up!


Looks like I'll be slowing looking for parts and if I come accross a whole truck I'll just buy that.
 
Chopping the frame and shortening it could easily be done in a day with the correct tools. Swapping the engine and diking with the harness will likely take days if one little thing is different sending you in circles.
 
ninerqb8 said:
The dash wiring is the same you need to swap the wiring from the firewall out and the pcm. That's assuming they are both a manual transmission. I have done the swap on a 98 truck it works fine.
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Conflicting info, but this intrigues me. My truck now is auto though, and the truck I'd be after will be auto. I obviously would swap out PCMs to the corresponding engines if I were to do this.
 
As long as they are both auto or both manual it should not be an issue at all.
 
I had to change the cluster on my 2000 along with engine wiring and pcm.
 
RickFox said:
I had to change the cluster on my 2000 along with engine wiring and pcm.
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So to clarify, along with seeing your sig, you dropped a 98' 12v with PCM and Engine harness into a 2000 chassis and body without a problem connecting the wiring?
 
AMS247 said:
So to clarify, along with seeing your sig, you dropped a 98' 12v with PCM and Engine harness into a 2000 chassis and body without a problem connecting the wiring?
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Yes, at first i just did the engine harness from where it plugs into the umderhood fuse block to the 98 12v pcm. With it like this I was getting a no bus signal in the 2000 Gauge cluster, but all the gauges and tach worked great. I finally found a 98 12v cluster just to see if that would fix my "no bus" issues and it cleared it right up.

Now as far as the auto trans working I cannot answer this as I run a manual vb. I was not sure if it would work and this was just an easier alternative. I have toyed with the idea of swapping in a normal vb just to see if it will work correctly, but have not had time.


Hope this helps you out.
 
RickFox said:
Yes, at first i just did the engine harness from where it plugs into the umderhood fuse block to the 98 12v pcm. With it like this I was getting a no bus signal in the 2000 Gauge cluster, but all the gauges and tach worked great. I finally found a 98 12v cluster just to see if that would fix my "no bus" issues and it cleared it right up.

Now as far as the auto trans working I cannot answer this as I run a manual vb. I was not sure if it would work and this was just an easier alternative. I have toyed with the idea of swapping in a normal vb just to see if it will work correctly, but have not had time.


Hope this helps you out.
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Awesome, that definately does. I would only think if I used my 98' 12v PCM, and maybe swapped transmissions as well I would be in the clear. I am wanting to go to a manual VB as well so even if it didn't I wouldn't be at a dead end!

If the engine harness from the 12v does in fact plug right in, and visa-versa that would be easy.
 
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