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Old 03-12-2010, 11:39 PM   #1
Join Date: Dec 2009
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Question NP231 question

Hey hows it goin everybody, I am working on swapping an 8.8 into my 94 yj. In doing so i realised that i would probably need an SYE. So I purchased an np231 out of what a think was an 02 wrangler, inline 6 w/ an automatic trans. Am I right to assume that the case will bolt up to my current trans? its manual, i think the ax-15 as i have the inline 6 also. Hopefully i didnt do something stupid, as i have already finished installing the sye on case. Thanks!!

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Old 03-13-2010, 09:48 AM   #2

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You need to make sure you have the correct spline count and input shaft length for your tranny. I would think you would be okay other than that.

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Old 03-13-2010, 10:37 AM   #3
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well i dont know what t case u got but the normal six cylinder spline count is a 23 spline input for the six and a 21 on the 4 Cly but i dont know if it changes on the auto to Manuel but i can tell u that for manual six Cly u need a 23 spline 231j so if u got the 21 u might have some troubles
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Old 03-14-2010, 09:42 AM   #4
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I may be wrong but I think the manuel & auto t-cases are different. You could call your local Jeep dealership & ask the service dept.
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Old 05-06-2013, 03:59 PM   #5
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Did anyone figure out if the trnsfercase from a manual trans to an automatic trans are swapable?
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