SPINE COUNTS and Input Shafts?

:new:

1998 XJ Sport
4.0 I6
AX Tranny

I want to swap my NP231 To an NP242

how do i figure out the input shaft spine count, (21 or 23)
and exposed length of the input shaft?
(.840
.750
1.550

please help

I'm new, so try not to flame me for my vast inexp in this forum


thanx

cipey:

Just count the splines! (some DIS-assembly required)
Ok, that was a bad joke.

The input shaft is actually the trans. output shaft. This shaft has to mate to the input gear in the T-case. When you swap t-cases, you usualy get a new gear to match the transmission.(output shaft on the trans is a living bitch to replace - full disassembly/rebuild - T-case input gear is much easier to swap)
Call a local jeep dealer and ask the parts counter. I think the AX-15 trans has a Id/Build number stamped on the bottom of it. If your jeep was built in a transition year, you may need to have that number to be sure, otherwise, they can just tell you.

I don't think you have to wory about the exposed length of the shaft as long as you stay with Jeep parts. They all have to mate to the -231, so they are all going to be about the same.
If there is a critical difference, about the only way to know for sure is to pull the T-case and measure.( I know, that does NOT help, but still,..) Slap a straight edge ruler on the end of the output shaft and measure back to the face of the extension housing - that's your exposed length.