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Old 10-03-2012, 07:37 PM   #1
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Is every np231 the same? Other than there's a 21 and 23 spline. Is there any electrical upgrades on the new ones? I have a 90 and the transfer case broke. The guy I'm buying one from says his has a plug on it and I don't think mine does?
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Old 10-03-2012, 08:10 PM   #2
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Yes I just ran into that issue,

They are both stamped 231J the one on the right is a 21 spline and the one on the left is a 23 spline.

[B]To be continued....:
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Old 10-04-2012, 12:41 AM   #3
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The newer one have a speed sensor instead of cable driven speedo is hwat i hear. But if you have an SYE no issue or you could just swap the tailcones. Yes 21 and 23 spline difference between the AX4/5 and AX15 trans 4 bangers and 6 bangers.
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Old 10-04-2012, 08:09 AM   #4
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you can just swap your mechanical speedo drive to the newer case. like posted 4 cyl cases have 21 spline , 6 cyl are 23. there was a gear change in the newer cases (94 and up) but thats internal.
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