I have a 1998 tj wrangler in the future I'm going to be swapping out my transfer case because I plan on putting a ax-15 transmission along with a 350 sbc or possibly a 4.0l. my current transfer case is a 231-j the case has the slightest Hair line crack by the check plug I tightened too tight when I changed the fluid I put jb weld on it and it's been fine... I bought a 1995 xj case to replace it because mines cracked and It has a true neutral like the tj case has also needed a 23 spline long input shaft for the ax-15 transmission instead of buying just the input shaft and another case I thought buying a 23 spline 231-j t case was a good idea... I may have goofed and at the time I was not aware the xj cases are clocked I have a slight understanding what it means but I'm not sure if it will effect me or not.. I have a 1 in transfer Case drop kit a tom woods double cardon drive shaft and a sye kit working on getting adjustable upper And lower control arms... do I need to be concerned with the clocking of the xj case or will it just be a direct Fit ? Would i need a ax-15 out of a 95 xj to make it work ? I'm also new to the jeep world and am trying to learn as I go so if this is a dumb question I do apologize Lol.... on another note I'm leaning more towards The 4.0l swap for several Reasons but I've been told and read I need to get a engine and trans from the same year as my current Tj so if I need to just sell the t case from the xj and buy one with 23 splines from a tj I guess that's what I'll have to do... hoping someone can chime in and help out
Transfer case compatibility
- Thread starter runninwild
- Start date
I meant I needed a short narrow spline for the ax-15 Long wouldnt work just not sure if clocking would be a problem idk if I need a ax-15 out of a tj or xj
I think we can help you but I'm having trouble comprehending your post..is there a chance you could shorten it up and post your question?
Look around a TC is cheap compared to an AX15, lots up there in PA. Assume you have the 4 cyn.
https://wranglertjforum.com/threads/yj-ax-5-in-a-tj.58105/#post-1025756
https://wranglertjforum.com/threads/yj-ax-5-in-a-tj.58105/#post-1025756
Last edited:
06TJ35's
TJ Addict
If you have a transfer case drop with a sye and double cordon driveshaft you need to remove the TC drop
Are you positive about this? A lot of cases have little hairline wrinkles in the surface leftover from the casting process.
from what I can tell, the clocking difference is accomplished by the hole pattern in the transmission trail housing, the transfer case bolt patterns are the same. I swapped the front half of an XJ 231 into my TJ and it went into the exact same position as it was before (as evidenced by it not contacting the tub or the skid once installed).
Wiring changed from year to year so it can make things easier, but I don't think it's that popular of a swap because it's still a swap, it's still time consuming and expensive and painful, so why go through the trouble just for the barely adequate 4L? Easier to just sell yours and buy one with the 6 cylinder.
@freedom_in_4low yes because when I was tightening it I heard a crack and it is right around the check plug dosen't Come out far but it is there...
@freedom_in_4low yes because when I was tightening it I heard a crack and it is right around the check plug dosen't Come out far but it is there
Basically what I'm asking about is when I do the swap am I going to have issues bolting a xj t case to a tj ax-15 trans? Only reason I'm questioning it is because of this clocking or deal from what I've read cloxking just moves your drive shafts Up or down if that's the case my adjustable Upper and lower control arms Should fix it if it is a problem
Are the Input gears the same spline count and length of stick out? The clocking is achieved by the trans flange not the transfer case
@tnjeepguy I'm ok with my transfer case and the small crack it's been fine for over a year. I'm not wanting to put a ax-15 In right now I'm looking to put it in when i swap everything over just trying to get my ducks in a row trying to make sure the transfer Case I bought is going to mate to a tj ax-15 Or a xj ax-15
it would raise or lower your front output yoke only. But more importantly it can't go too far before the top of the case hits the tub floor or the bottom hits the skid plate.
But as I indicated, the clocking is done at the transmission output, not on the front of the transfer case. I've installed an XJ 231 on my AX15 TJ with no problems, then moved it over to my NSG370 LJ. The only difference was that it came from a different transmission so I changed the input shaft to go on my AX15. It was clocked the same as the one I removed.
I've seen earlier cases with a different output, not sure if it's just the housing or if it's the shaft as well.
narrow? They come in short, medium, and long. Novak incorrectly reports that the AX15 requires the short input but it actually takes the long input. I'm sure there are plenty out there following Novak's advice and they don't have as much spline engagement, but I haven't heard of anybody twisting the output shaft off or stripping the splines, so it's probably fine.
@freedom_in_4low well... that's who I'm getting all my build info from.. yea they told me I need a short narrow gear input shaft on the t case so I went and bought one and thought I was ok
Here's the thread I made about it at the time. My 99, 4.0L AX15 TJ 100% had a long input, and the 2000 AW4 XJ case had a short input, both of which conflicted with Novak's chart.
https://wranglertjforum.com/threads/long-np231-input-gear-on-an-ax15-transmission.30744/
Here's another thread where it's discussed with respect to the 32RH requiring a long input vs short (Novak 0, Reality 3)
https://wranglertjforum.com/threads/32rh-to-nv3550-swap-on-2002-tj.59228/page-2#post-1052849
To make things even worse (for Novak), I've since discovered they're even wrong on the NSG370 - my LJ had a case with a short input and Novak says it takes the long. The good news for me is that the long input still fits so I didn't have to split a transfer case again. So for every transmission they list for a TJ, they're wrong...they don't show the 42RLE but if they did, it would probably wrong too (it takes a short input)...it's like an intern mixed up the definitions of the words "short" and "long" when they made that page. Or maybe they're using short and long to describe the transmission output shaft but then labeled the chart for the TC input.
All that said, thanks to Novak's page I'm sure there are tons of people running around with short input 231's on AX15's and I have yet to hear or read about somebody stripping the splines or twisting off the transmission output shaft, so you're probably ok with the short 23 spline.
here's another post where we got some detail on what should be, straight from Mopar's parts books.
https://wranglertjforum.com/threads/np231-transfer-case-differences.9828/page-2#post-934548
Basically, for a 4.0L 231, 03-06 all came with short inputs, and 97-02 all came with long inputs, and the change coincided with the introduction of the 42RLE which would suggest it can't use a long input, so for simplicity they just switched everything over to short.
Which means:
1. AX15 only came with long but probably works ok with short
2. 32RH requires long but can be adapted to short with a seal extension
3. NV3550 came with either depending on the year
4. NSG370 came with short but will accept a long
5. 42RLE only came with short and very likely requires short
https://wranglertjforum.com/threads/np231-transfer-case-differences.9828/page-2#post-934548
Basically, for a 4.0L 231, 03-06 all came with short inputs, and 97-02 all came with long inputs, and the change coincided with the introduction of the 42RLE which would suggest it can't use a long input, so for simplicity they just switched everything over to short.
Which means:
1. AX15 only came with long but probably works ok with short
2. 32RH requires long but can be adapted to short with a seal extension
3. NV3550 came with either depending on the year
4. NSG370 came with short but will accept a long
5. 42RLE only came with short and very likely requires short
@freedom_in_4low ok thanks maybe I'll check on here first before novak if I have questions. I've been told its easier To buy a complete 4.0 donor vehicle but I dont see why I couldn't just buy A 4.0l engine that had a standard transmission and no skim all the wiring harnesses And buy whatever year ax-15 I can find and that should be It right ?
As far as bolting it together, yes that'll work. The reason it's said to buy a complete donor is because generally, you can buy a donor, take all the parts you need, and then sell what's left and end up spending less than sourcing all those parts individually. Also, when doing a swap, it's virtually impossible to predict EVERY part that you need and it's easy to waste a ton of time and money hunting down little stuff that you would have had if you'd bought the donor. For example...I have no idea what differences might exist between the 4 cylinder and 6 cylinder in the fuel system or evap system, the HVAC, etc.
The 4 cylinder had different motor mounts, so you'll have to cut those off and weld 4.0 mounts onto the frame, just like any engine swap. I haven't done a swap on any modern fuel injected vehicle so I can't speak to how well the harness integrates into yours (or when you say all the harnesses, do you mean ALL the harnesses?). I get the impression it's not like a GM crate motor with a standalone engine harness, and I also get the impression that in the end it ends up not that much, if any, easier than swapping in a completely different motor that never came in a Wrangler. There is the compatibility with your gauge cluster, which is nice, but you can get that with a V8 from a Ram pickup if you get the right year. And a 20+ year old Ram donor is probably cheaper than a Wrangler at this point, anyway.
To put it more succinctly, I'm not aware of anyone on this forum having completed a 4cyl to 4.0 swap in a TJ, but there are numerous V8 swaps, even a diesel or two.