Will a 231 transfer case from a 1997 TJ bolt up to my 2004 TJ?

BiggRiggs

BiggRiggs

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New to the forum so thanks in advance. I have a 2004 TJ X 4.0L manual transmission. My transfer case is roaring terribly. I have purchased an used transfer case from a 1998 TJ 4.0L manual transmission. Will this bolt up directly or is the input shaft on the 04 longer than the 98. If so can I just buy a SYE kit for an 04 so that that the main shaft of the transfer case is replaced. In other words what’s my best options here.

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So instead I just ordered a gear shop remanufactured. However, when they invoiced me it said 23 spline short input. I questioned them on it and gave the all documentation that would indicate me needing the long input shaft. They’re currently checking into it to verify what I need. My question is, is there any way that I would need the short input shaft. I see on their invoice the are just going by 96 and up. The whole thing scares the hell out of me because if they can’t figure out what I need how good of a shop is it. I’ve attached the invoice
 

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Weird. Don't people swap in AX-15s to replace their NV3550s all the time without worrying about short vs long shaft?
 
BiggRiggs said:
So instead I just ordered a gear shop remanufactured. However, when they invoiced me it said 23 spline short input. I questioned them on it and gave the all documentation that would indicate me needing the long input shaft. They’re currently checking into it to verify what I need. My question is, is there any way that I would need the short input shaft. I see on their invoice the are just going by 96 and up. The whole thing scares the hell out of me because if they can’t figure out what I need how good of a shop is it. I’ve attached the invoice
Click to expand...
I can only say that for my AX-15 transmission that the 231's input shaft was the short version. For the 32RH automatic the 231 was configured with a long input shaft. I don't know newer transmissions required different lengths of 231 input shafts from what my '97 TJ required.
 
There is no single source or ultimate NP231J compatibility guide. However, all 2003-2006 NP231s in TJs had a short input gear. The AX-15 also required a short input gear NP231. Simple in terms of compatibility.
 
You just said both take
AjRagno said:
There is no single source or ultimate NP231J compatibility guide. However, all 2003-2006 NP231s in TJs had a short input gear. The AX-15 also required a short input gear NP231. Simple in terms of compatibility.
Click to expand...
So you’re saying all TJ’ with NP231 require the short input shaft
 
AjRagno said:
There is no single source or ultimate NP231J compatibility guide. However, all 2003-2006 NP231s in TJs had a short input gear. The AX-15 also required a short input gear NP231. Simple in terms of compatibility.
Click to expand...
To clarify this... I've been looking at options to replace the transfer case in my '05 LJ with the 42RLE for a while and I've come across a lot of information. According to Novak the AX15 requires a short input gear. However, if you look around you'll find owners who say that the transfer case connected to their AX15 had a long input gear. I suspect that rebuilders and resellers are using short input gear because it works across all TJ years(?). I was not correct in saying all 2003-2006 NP231s in TJs had a short input gear. It was the automatics that had the soft input gear.

From Dead Jeeps:

4.0 Wrangler TJ NP 231 J Transfer Case 272 Ratio 23 Spline Short Input

4.0 Wrangler TJ NP 231 J Transfer Case 272 Ratio 23 Spline Short Input, this will fit all 6 cyl Wranglers STANDARDS 97-06 as a direct bolt in. Also fits ALL 03-06 automatic wranglers. Input shaft is a 23 spline short which means it sticks out 7/8ths of an inch past the seal. Standard Wranglers 97-04 also used a long input and are interchangeable.

97-02 Wrangler TJ NP 231 J Transfer Case 23 Spline Long Input

This will fit all ALL 4.0 6 cyl Wranglers 97-02 as a direct bolt in whether an automatic or standard. Also ALL 4 cyl AUTOMATICS ONLY 97-02. Wrangler 4cyl STANDARDS have a 21 spline input. This is a 23 spline long with means input sticks out 1 5/8ths of an inch past the seal.
 
Adding to this thread for anyone searching this topic in the future. Below are pics of a short and long as well as an AX15. In this case, the person is swapping out a 231 for another 231 that already has a SYE on it. His original t-case has the long input whereas the replacement t-case has the shorter input. Measurements say it should work. For those with experience about this topic, will the short input definitely work when the prior t-case input was long?

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Found this answer in a different thread (y).

"The transmissions in any TJ only need the short length input to clear the sealing surface in the rear of the transmission. The medium length input will also fit into any of the transmissions. The long length input will fit into The AX15, NV3550, NSG370, and 42RLE. It will not fit inside the 32RE however. So the transmission that you have can utilize any of the 3 input lengths. The late TJ's did however most commonly come from the factory with a long length input. That doesn't mean it's what has to go back in, in order to function as designed. I can however build you one with a long length input if you are more comfortable purchasing that one. I know, it's clear as mud. It's taken me a long time and building hundreds of these in order to figure out what books don't tell you."
 
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hosejockey61 said:
Found this answer in a different thread (y).

"The transmissions in any TJ only need the short length input to clear the sealing surface in the rear of the transmission. The medium length input will also fit into any of the transmissions. The long length input will fit into The AX15, NV3550, NSG370, and 42RLE. It will not fit inside the 32RE however. So the transmission that you have can utilize any of the 3 input lengths. The late TJ's did however most commonly come from the factory with a long length input. That doesn't mean it's what has to go back in, in order to function as designed. I can however build you one with a long length input if you are more comfortable purchasing that one. I know, it's clear as mud. It's taken me a long time and building hundreds of these in order to figure out what books don't tell you."
Click to expand...

Who posted that? Link to the thread?
 
Damn so I have an 04 LJ with the 231 and 42RLE and a guy I know has a 231 out of his 2001 with the 32RH that already has an SYE. I wanted to buy it but it doesn't sound like it will work? If I understand it, I have the short shaft and his is the long one?
 
For BiggRiggs‘ and Steelydan‘s SYE questions with regard to long vs short input shaft on 231J:
The 231 input shaft is also the input gear. It protrudes out of the front of the case past the input seal and engages the transmission output shaft. the other end of the 231 input shaft and gear has a needle bearing that the rear output shaft(mainshaft) forward end rides in. The rear output shaft exiting the rear of the 231 is splined for the slip yoke forward end of the rear driveshaft. Or the splined output shaft is replaced with a shaft with ujoint yoke-this is a slip yoke eliminator (SYE). Therefore the 231 input shaft (short or long) is not impacted by whether the 231 has a splined output shaft or a SYE. It took me a while and rebuilding my 231 to learn this. TJBUD
 
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