NP231 23 spline to 21 spline -
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post #1 of 4 Old 03-01-2007, 09:10 PM Thread Starter
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NP231 23 spline to 21 spline

Can the input shaft on the NP231 be easily changed from 23 spline to 21 spline.
The reason I ask is I found a good deal on a 231 with a tera low installed but it has the 23 spline input, I have the AX5 transmission in a 97 4 banger.


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post #2 of 4 Old 03-26-2007, 02:07 PM
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post #3 of 4 Old 03-26-2007, 05:13 PM
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you're looking at a complete disassembly of both cases to swap it out. or just one if you want to spend the $$ and buy a new input gear. but yeah, it can be done.

RIP: '88 YJ 2.5L Ax-5 NP231
Posi-Loked. Herculined. Optima yellow top. 1" Shackle, 2" BDS. Cragar 397's Aussie front.

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5" springs, 1" shackle 31's or 35's depending on my mood
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post #4 of 4 Old 03-26-2007, 10:40 PM
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I'm not 100 % on this .
but if the old t-case is the 2.72
and you want to go to 4:1 .the input shaft off the old case won't line up to the planetarys of the 4:1
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