XJ Transfer Cases

[MSS]

Does anyone know if NP231 and NP242 Transfer cases are interchangeable (behind an AW4)?

Do they have the same input spline count/length, mounting bolt pattern, etc?

 

[Brett]

Does anyone know if NP231 and NP242 Transfer cases are interchangeable (behind an AW4)?

Do they have the same input spline count/length, mounting bolt pattern, etc?

They are interchangeable. Depending on the year, you might have to change the input gear on the transfer case, but other than that, no difference

 

[MSS]

cool - thanks for the input

Anyone have experience with the NP 242? Any issues or things to look out for? I like the idea of the AWD mode for a driver.

 

[Brett]

cool - thanks for the input

Anyone have experience with the NP 242? Any issues or things to look out for? I like the idea of the AWD mode for a driver.

I like mine and have never had any problems with it. Just wish there were a few more tailshaft conversion options. I am pretty sure Tom Woods is the only one that offers a SYE for it

 

[ewander]

If you do need to change the input from a 21 spline to a 23 spline you can take the existing one from your 231 and it "should" be interchangeable.

From NAXJA.org-
Should be, I have a manual. But helped out on a swap with the AW/4 and a 242 from a AW/4 and a 231 and it was plug and play, I looked at Novak and it appears it should bolt right up and the electronics are the same.
heres the site
http://www.novak-adapt.com/knowledge/aw4.htm

also:

http://www.naxja.org/forum/showthread.php?t=65090&highlight=NP242+swap

Eric

 

[Herzog]

Other than no aftermarket options for a 4:1 range kit and limited tail shaft conversions, the 242 is a great case. It worked extremely well on snowy pavement when my XJ had that case. The full-time option is nice to have.

Mine was an '89 21 spline. Some of the years for the input splines are kinda weird... to completely sure what you have, best thing to do is pull it and count.