NP231J trasfer case noise

[JammedJeep]

Hey, so my np231j transfer case on my tj broke so I got one from the junkyard but it had a short shaft so I put the planetary gear from mine to the new one and replaced all the seals. It works great but there's a whining noise almost like straight cut gears and it gets worse the faster I go. I flushed the transfer case oil and still makes the noise. I suspect it's the planetary gears because the sound is coming from under the shifter. I'm wondering, should I be concerned? And why would this happen?

 

[macleanflood]

There is a break in planetary gears around 96 I think. Others know more.

When I broke the front half of my case I ended up with an early 90s Cherokee box...I ended up mashing together parts to make something work.

I thought I made a video...hmm... might have to check my folders and see why I didn't upload it.

-Mac

 

[Rickyd]

There is a planetary gear design change around 1995. You haven't said what came out or what went in. Can't help much other than to say its either incompatible or you put another broken tcaseback in

 

[JammedJeep]

There is a planetary gear design change around 1995. You haven't said what came out or what went in. Can't help much other than to say its either incompatible or you put another broken tcaseback in

It came from a Cherokee of the same gen idk exactly what year though.

 

[JammedJeep]

It came from a Cherokee of the same gen idk exactly what year though.

And my tj is a 1999 year