Atlas 5.0 into XJ, with a TJ AX-15

Long story short I swapped the AW-4 out for an AX-15. I was told it came out of a 98 XJ. Turns out it is a TJ AX-15. It started leaking bad between the t-case and trans. What I have researched and found is that my np-231that came in my auto equipped XJ uses a short 23 spline input. So what I gather with that is that the input is not properly engaging the trans seal, causing it to leak.

I have now ordered the Atlas 5.0. I figured that I would need the long 23 splind input that Is listed on their site as an option. However, when I called and talked to them I was told there is only 1 23 spline input they have. I was then told I would need to trim 1/2" off the trans output. What I am wondering is can I use the 1" spacer? Will it have the proper seal engagement on the trans, since it appears I would need a long 23 spline input for a np-231? Does box this make sense or sound correct?

Here's a few links I had when I researched the AX15/Atlas.


http://www.naxja.org/forum/showthread.php?t=1039150

http://www.naxja.org/forum/showthread.php?t=24618

http://www.naxja.org/forum/showthread.php?t=16517

I appreciate the links! I have seen the first one but the 2nd 2 were new to me. I Just found another write up that was done on a TJ. Based no what it said, it is normal for the input shaft to not reach the seal on the trans. It looks like you seal off the weep hole on the trans flange and then actually seal the t-case to the trans. The Atlas has a dual seal on the input and is for that reason. Does that sound right to anyone who has installed an Atlas?

Tera-flex used to sell an extension seal,they still show it in their installation instructions.
Sorry link didn't work!

RCP Phx said:

Tera-flex used to sell an extension seal,they still show it in their installation instructions.
Sorry link didn't work!

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Yeah I saw that. I did some more research and found some threads on Pirate about it. It appears to be perfectly fine to seal the weep hole and seal the Atlas to the trans. The Atlas is dual sealed on the input specifically for that so hopefully it won't be any sort of an issue. I can't wait to get it, 87:1 1st gear CR! :-D

live24wheel said:

Yeah I saw that. I did some more research and found some threads on Pirate about it. It appears to be perfectly fine to seal the weep hole and seal the Atlas to the trans. The Atlas is dual sealed on the input specifically for that so hopefully it won't be any sort of an issue. I can't wait to get it, 87:1 1st gear CR! :-D

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It isn't an issue as long as you seal the weep hole really well. Ive actually had the Tera seal extension for many years but never felt like pulling the case back off to install it.

I had an issue with leakage before I put my Atlas 4 sp in. I called Advance Adapters and they sent me a steel ring to be used with two gaskets that cured the problem. If your shaft is really that much too long, just trim it a little. It will make no difference in strength since there are plenty of splines in the tcase input.