I have a 2001 XJ sport, with a np231 tc, I installed a rough country Sye and it seemed fine at first, still I heard a rubbing noise and found lots of metal shavings in my transfer case.
​case. So I took it to a transmission mechanic, they Open to the case and found out that the chain is binding and rubbing on the gear below it, And we can't find out why. This is been day four without a car. It's exactly the same problem as this person was having on his jeep (link and photos here) but nothing here as worked, or that I understand.

I was hoping somebody could shed more light on this problem, as that thread is 10 years old. And from what I understand the newer transfer case is should be mostly plug and play with a sye. I have contacted rough country, And they have been ignoring emails and phone calls from me for days. So I'm kind of at a loss for what to do.

 

RTV on the chain, sloppy!

Ok, so the sprocket shown is to high up the shaft. So either drop it to fit, or maybe shim the other sprocket up to match, or get better fitting parts.
This should have been caught when the new parts were installed, I guess that shop failed to check how things rotate and line up.
Glad you caught it. Hopefully the shop that has it now is the not same as the first shop that installed your new ill fitting parts

Was it making a lot of noise? How you know to take it out?
Good catch on your part, but Id stay clear of the shop that did this, yikes!

My jeep dont run chains, except on my tires. How about upgrading to a chainless Atlas transfer case? They are sweet, all gear drive, and syncromeshed! wide range of gear ratios possible, two or four speed Hi hi, Hi Lo, or Lo lo.. mine is a 2 speed, 4.11 Lo range. I like it.

 

I'm with robsjeep I think you should be able to shim the gear or the shaft to stop it from rubbing and clean out all the RTV out of the in side , there is a oil pump in the T case .

 

Thank you guys so much for this suggestions and help, My mechanic just called me and told me he figured out how to fix it and I could pick it up Monday afternoon 2 days from this post, so when I go get it from him I will see what he did and post that here for anybody else who had this problem!

 

Did you ever find out what your mechanic did to fix this issue, I haven't been able to get mine to stop binging. I also used the rough country sye kit, and now I've gotten all new bearings seals and a new G2 gear (100$ more than the RC one) sye kit. But I'm still getting this issue. It's day 5 for me.

 

are you really responding to your own post?

 

Oh my GOD, I'm so stupid bro. Yeah I guess I really did reply to my own post I've been having this problem for a while. Anyways in case anybody was curious or having this problem I did figure a solution out.

So the mechanic that I took it to with some driveline shop down in Denver and they lied to me telling me they fixed it and never actually did anything. So it was still grinding and still binding on the chain. They just told me everything was fine.

Turns out my rear drive shaft had seized at the slip joint. So when I was hitting bumps it was knocking the yolk and shaft of the SYE back into the transfer case. This caused the bearing housing that sits on the other side of your planetary gear in the transfer case to slide too far backward causing the chain to bind on your selector fork gear. After a while of thinking everything was fine. The seized joint ended up blowing the pinion bearing in my rear axle as well as to separating the weld on the yolk and ruining the bearing of the SYE kit. (It was rough country)

I have now since totally tore down the np231j transfer case, (4th time, I'm wayore confident about it now) replaced the bearing housing and set it to the correct depth. And installed a new G2 gear SYE kit, swapped out the rear axle for a Chrysler 8.25. and got a Tom woods custom length drive shaft. The ride quality is a lot smoother It's a lot nicer. Even made sure my opinion angle was spot on.

Due to the metal shavings and stress on the transfer case, My planetary gear has quite a bit of gear lash and isn't the quietest in 75+ mph, (does Jeep need to go that fast anyway) It is only the three pinion that came stock for the 2001 model, so when money becomes more available I'll throw a six pinion planetary gear maybe even do a 4:1 with the 1.25 chain upgrade.

It's something I'm ashamed to admit I didn't catch. But it is my daily driver. Between a full-time job and college. Trying to rebuild an entire transfer case in one night and trying to figure everything out is not the easiest when I have little to no experience and I'm by myself.
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as for now I've got a new problem, I use my winch to get some people out of a muddy mess, and heard a loud snap from my front end. haven't been able to identify it yet. But I'm sure I'll find it when something either fully breaks off or while I'm doing my OTA track bar to match my OTK steering

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