I just put a Cummins from an 05- 2500 into an 04 and went to plug the harness in and I've got two male plugs on each side . Can I switch the engine compartment harness that plugs in under the dash and the truck will run?

 

So nothing is the same and I'm gutting everything from both trucks and swapping it out. The throttle in the 05 is electric and the 04 is cable ..

 

Based on your posts with very limited info..

It sounds like you are trying to install a 2005 Cummins engine into an early 2004 Dodge Cummins.
If the truck was a 2004.5 it would be plug and play but since you are into harness compatibility issues, the truck must an early 2004, not a 2004.5.
Dodge made significant changes mid-year (Jan 1, 2004) back then.
There are some minor changes between the 2004.5 and 2005 trucks also.

There are numerous threads on guys doing exactly this. Some guys have swapped the entire harnesses, the ENTIRE truck harness to make it work.
I don't recommend that. You end up with a mickey mouse, mismatched truck.

I recommend putting 2003-04 pistons and 2003-04 injector nozzles in your 2005 engine and then drop that into your early 2004 truck.
That's not so easy but would keep your 2004 truck's ECM and harness original.
This turns your 2005 engine into a 2004 engine compatible with the programming in your 2004 ECM.
If the 2005 is original, this makes for a really stout engine. The 2004.5+ cylinder head is better than the 2003-04 cylinder head, but the 2003-04 pistons are better than the 2004.5+ pistons.

Another option is to drop your 2005 engine into your early 2004 truck, keeping the 2004 ECM and harness original.
Then reprogram your 2004 ECM with a 2005 program to run the 2005 truck.
Not easy either but it has been done. You will need a Smarty Touch or HPT programmer and someone to write the program and likely make changes.

This is exactly what Green Machine did. The 2003 and early 2004 trucks are nearly identical.

https://www.dieseltruckresource.com/...stions-331604/

I hope this info helps...

 

Yes . Unfortunately I have already swapped the entire truck harness's and are putting the 04 back together.fornunately I've been building cars and trucks my entire life . It's a big job for sure but I think I have it handled..I also got the 04without the engine and running gear ....

 

Hopefully the 2 trucks are both of similar configurations.

You will likely have to swap the dash also. If I remember correctly, all the 2005+ trucks have the SKIM security system, ie. RFID chip in ignition key.
You will have to swap the SKIM transceiver in the steering column, if not the entire column also.

Good luck... After this swap, just call your truck a 2004.5 from now on!

 

Hey thank you for your knowledge. You definitely know what your talked about..and yes I'm swapping the dash,column ,**** near everything.. luckily the body shells are the same but that's about it..had I been aware before hand I would have suggested finding an 04 correct engine but I came in after the swap was started and didn't know about the changes untill I had the engine in . Like I said there was no engine in the 04 and the 05 was partially tore apart.. both were bout at auction and it was assumed they were comparable.. I'm about halfway done and have a good 40 hours in it this far.. I even had to swap the pedals to make it work.. again thanks and id love to be able to get advice if needed as I continue.

 

Sounds like both trucks got lucky in finding you to bring one back to life...Keep us informed on your progress......Ben

 

Thanks Ben ill definitely keep y'all posted and let you know when is running!!!

 

I have a 2006 in a 2003 dodge

You need a 2003-2004 wiring harness. You should have it from the old engine.

Also swap the injector plugs assembly from the 2004 to the new engine

then simply use the old harness on the new engine. Everything is identical except the coolant temp sensor. Again just swap the old sensor into the new block

no need to change pistons. Old wives
tale

no need to change programming. It turns out that although the early and late ecms have the same tables they use them differently. In other words there is no way to match up the old ecm to the new one by altering settings to the same numbers. Trust
me on this. Early stock ecm runs the new engine just fine



no need to change injector tips

You can use the new style turbo if you want. Just wire the solenoid to 12volt ignition and you’ll make about 30lbs of boost

eaay right?

chay

 

Thanks for the reply . Unfortunately I have already done the entire harness swap on the dash etc.. I don't have the 04 engine because the truck was purchased without the drivetrain.

 

Gotcha. That's too bad. Lots of work!

Hope it finished up easily.

Chay

 

Well, IMO, there is some terrible info in your post about matching injectors/pistons and programming. Especially since your other posts show some technical skill and prudent decisions.

I checked but I don't see any updates to your other threads. I don't see any updates with your obvious struggles with your own engine swap and programming challenges.
Sorry to hear that.


Yup, you can throw any engine together, mismatched components and all, fire it up, call it good and close the hood.
Anyone can do that and that's fine if you want to do that but there is no need to recommend that to others.


Just my thoughts..

 

Well I've done the entire swap of the engine. With all the wiring and electrical components.. I've got everything from the 05nto to the 04 and it's working well.. alot of work yes but it's now a good truck.running fine...

 

StealthDiesel, I'm sure it comes as no surprise that I'm dissapointed in the closed mind attitude you seem to have.

To be clear, running the 04.5+ injectors in the 04.5 engine with the 03-04 ecm is not an issue. IE: Match the injectors to the piston profile you have.

As far as bad information, well the forum will have to decide. I've always valued actual experience more than speculation and supposition.

Some of us don't have the time or money to match pistons, and injectors to the original spec, especially when it's not necessary. We have to get our trucks back on the road in a timely and cost sensitive manner. And this works well. **** right I'll recommend it to another guy in my position.

And by the way, I'm not breaking new ground here. I have bumped into at least two others that have done the same thing with long term success.

Chay

 

Let's just agree to disagree and leave it there!