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?
They are both stamped 231J the one on the right is a 21 spline and the one on the left is a 23 spline.
10-03-2012 11:41 PM
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.
10-04-2012 07:09 AM
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.