jkw

Hey all, does anyone know if a yj np231 will work I'm my xj? I found one with a sye faily cheap.
Thanks

Elexwiz

Yup, an NP231 is an NP231. They're not model specific. Now depending on the tranny in the YJ and XJ, you may need different bell housings, etc. But the xfer case is the exact same.

jkw

thanks man, ill see if i cant still snag this one

OttawaXJ

Actually if I recall they're different spline counts... Also I believe the YJs are vacuum actuated aswell.

dogger15

Just take the sye out of it

fedx95

be careful with the clocking. I don't remember if the transmission holes or the transfer case holes are different. The transfer case may sit clocked different and hit your floor. I say take the sye out of it.

mud-dog27

spline count is only relevant to what engine it was behind, 4cyl were 21spline 6cyl were 23spline as far as YJs go

the clocking ring is on the transmission not the tcase, as second poster said an np231j is an np231j whether it was in an xj/mj/yj, only time it differs is when we are talking gm/chev or dodge 231s.

also the YJ will have the vacuum 4wd switch, im not sure what tcase OP is running so that may be another difference if its the 242 in OPs jeep but its just a matter of swapping switches.

fedx95

thanks for the clarification!

ol'DixieJeep

i got mine from a tj with a SYE and the input shaft was too long. had to get the one out of my busted one and swap em.

TheNerd

There are something like 6 potential input gear options for the NP231:

http://www.novak-adapt.com/knowledge...nput_gears.htm

Some are much more common than others, but all np231s are not *exactly* alike. That being said, they are pretty simple to work on and the worst case is you need to swap out an input gear (as mentioned). Not too much work.

mud-dog27

ah thanks, i completely forgot bout the input shaft lengths, but yea they are pretty easy to work on and swap parts.