5.9 Swap Preliminary Research Questions

AlaskanTJ

AlaskanTJ

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Original poster
Joined
Feb 18, 2026
Messages
4
Location
Alaska
I'm looking to get started on swapping a 5.9 Magnum into my TJ in the next couple months, and I wanted to try and get answers to some questions I haven't been able to answer just from scouring various forums. Here's what I'm working with to start with:

2001 TJ Sport
4.0 Auto
Dana 44 Rear
4 in lift with T-case drop brackets

Donor Vehicle is a 2003 Ram 1500 5.9 Auto

Some initial questions I have:
The Ram has functional Cruise Control, but my TJ did not come with it. Am I going to need to add wiring on the body side to get it to work, and would I need a newer year's steering wheel? Could I use the Dodge's, as silly as that would look?

I was able to get a ZJ 46RE for free, but I am unsure from my reading as to whether or not the newer PCM will be able to control it. I'm pretty sure the older 46RE's don't report gear position, but I figured that wouldn't be an issue as my TJ doesn't have that dash functionality to begin with. Any ideas on whether that could be adapted, or should I just stick with the Dodge 46RE?

My Jeep uses a chipped key, but the donor does not. Will this be an issue, or will I just leave the Jeep's security wiring out of the picture?

Should I just get the SYE thing out of the way now? I assume I'm going to need custom length driveshafts anyway with the AA motor mounts, so it seems prudent to do it now rather than later.

That's all I've got at the moment, but I may have more questions later on. I just want to build up as much of knowledge base as possible before I get started.

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AlaskanTJ said:
I'm looking to get started on swapping a 5.9 Magnum into my TJ in the next couple months, and I wanted to try and get answers to some questions I haven't been able to answer just from scouring various forums. Here's what I'm working with to start with:

2001 TJ Sport
4.0 Auto
Dana 44 Rear
4 in lift with T-case drop brackets

Donor Vehicle is a 2003 Ram 1500 5.9 Auto

Some initial questions I have:
The Ram has functional Cruise Control, but my TJ did not come with it. Am I going to need to add wiring on the body side to get it to work, and would I need a newer year's steering wheel? Could I use the Dodge's, as silly as that would look?

I was able to get a ZJ 46RE for free, but I am unsure from my reading as to whether or not the newer PCM will be able to control it. I'm pretty sure the older 46RE's don't report gear position, but I figured that wouldn't be an issue as my TJ doesn't have that dash functionality to begin with. Any ideas on whether that could be adapted, or should I just stick with the Dodge 46RE?

My Jeep uses a chipped key, but the donor does not. Will this be an issue, or will I just leave the Jeep's security wiring out of the picture?

Should I just get the SYE thing out of the way now? I assume I'm going to need custom length driveshafts anyway with the AA motor mounts, so it seems prudent to do it now rather than later.

That's all I've got at the moment, but I may have more questions later on. I just want to build up as much of knowledge base as possible before I get started.

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First off welcome to the forum.

Where in AK? Lived in Barrow as a kid and stationed @ Ft Richardson in the early 80's.

We need the build date on your TJ. Jeep switched between CCD bus and PCI bus mid year 2001.
That will determine if the PCM from the truck will work in your Jeep.

The year of the transmission doesn't matter.
You'd need to wire the Jeep for CC. And as far as I know the Ram steering wheel wouldn't work.

Don't do the SYE until you're ready to do the swap. You might or might not need to change your driveshaft length.

You do want to do a body lift for transmission clearance.
 
NDSpeed said:
i thought the 5.9 was too wide for the rails, or was that what your last motor was @Wildman
Click to expand...

5.9 is the same size as the 5.2. Only difference between them is the drivers side motor mount.
And yes the engine that the block cracked was a 5.9 with a stroker kit. Making it a 6.7.

5.2's rev faster where the 5.9 revs slower plus runs warmer.
 
Wildman said:
First off welcome to the forum.

Where in AK? Lived in Barrow as a kid and stationed @ Ft Richardson in the early 80's.

We need the build date on your TJ. Jeep switched between CCD bus and PCI bus mid year 2001.
That will determine if the PCM from the truck will work in your Jeep.

The year of the transmission doesn't matter.
You'd need to wire the Jeep for CC. And as far as I know the Ram steering wheel wouldn't work.

Don't do the SYE until you're ready to do the swap. You might or might not need to change your driveshaft length.

You do want to do a body lift for transmission clearance.
Click to expand...

I live in the MatSu area, so nowhere near Barrow, but not far from Ft Rich. I'll have to check on the build date when I'm back home, but if I had a CCD bus what would that entail? Major harnesses changes? Just the PCM? As for the SYE, I meant should I do it as part of the swap, not as something to be done before.
 
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AlaskanTJ said:
I live in the MatSu area, so nowhere near Barrow, but not far from Ft Rich. I'll have to check on the build date when I'm back home, but if I had a CCD bus what would that entail? Major harnesses changes? Just the PCM? As for the SYE, I meant should I do it as part of the swap, not as something to be done before.
Click to expand...

The difference if it's CCD or PCI would be a different PCM.
Or swapping out the wiring harness.

PCM swap is much easier.

I'd forgotten to mention your chipped key question.
If you connect a PCM that doesn't have security enabled it will do so once connected.
As far as I know you can't turn the security off once enabled.

And with the auto swap most times you don't need new driveshafts but better safe than sorry.

There's a thread on JeepForum about doing the Magnum swap. I'll post a link for it once I'm home.
Plus a couple others.

If you have any more questions please ask.
 
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Wildman said:
The difference if it's CCD or PCI would be a different PCM.
Or swapping out the wiring harness.

PCM swap is much easier.

I'd forgotten to mention your chipped key question.
If you connect a PCM that doesn't have security enabled it will do so once connected.
As far as I know you can't turn the security off once enabled.

And with the auto swap most times you don't need new driveshafts but better safe than sorry.

There's a thread on JeepForum about doing the Magnum swap. I'll post a link for it once I'm home.
Plus a couple others.

If you have any more questions please ask.
Click to expand...

So does that mean my Jeeps chipped key will assign itself in the Dodge's PCM? Also I've been collecting forum post bookmarks, so I'll take any useful ones.
 
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AlaskanTJ said:
So does that mean my Jeeps chipped key will assign itself in the Dodge's PCM? Also I've been collecting forum post bookmarks, so I'll take any useful ones.
Click to expand...

I've never done it so I'm not 100% sure but that is what I've read.

I've got a lot of Magnum information to share.
I did my first swap in 2006.
 
AlaskanTJ said:
Just checked the door sticker, Sept 2000 is the build date. Where does that fall?
Click to expand...

That means it's a CCD bus. Which means the PCM from your 2003 truck won't work.
You need a 2001.5 or older PCM. Year doesn't matter but you want it from a base model truck.
 
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