Today my stepfather and I performed the 249 to 231 Transfer case swap on my 95 Jeep Grand Cherokee.  We had to swap the input shafts and all seem to go well.  We filled up the Tcase, topped off, the transmission fluid and I take it for a test drive.  All goes well until I try to shift the Tcase through the gears.  The Tcase wouldn't shift.  After yanking it back and forth it finally shifts to 4LOW.  Then when I try to shift it back into 2WD it the shifter would not shift.  After driving the last quarter of a mile to my house and messing around with the Transfer case shift linkage we managed to notice that the case would shift find and then we would move it and it wouldn't shift.  After messing around with the Tcase for a while we thought back to when we were reassembling the Tcase and we remembered that couldn't remember which way the syncro gear went in.  We now are not sure which way we put it in, but I am wondering could putting it in backwards cause this problem? Please help we are removing it again tomorrow and tearing it back down and I need ideas of what to look for.  

The 4lo does not have a syncro. The trans should be in neutral, and the vehicle should not be moving to shift into 4lo.

The 2wd to 4hi does have a syncro and should be able to shift on the fly.

The linkage is tricky. To adjust the shifter linkage bell crank clamp, the TC needs to be in 4lo. The shifter inside the cab should be in 4lo with a little room before it contacts the console.

I asked about your shifter in a previous post last week, but you did not answer. Your shift gates may not be compatable. I'm not familiar with the 249 Grand setup.

I think you have either an incompatible shift gate or a linkage adjustment problem, not a TC problem.  

Also, the syncro is on the main shaft. In order to replace the input gear you would not have to remove any of the gears from the main shaft. So, I'm not sure what you are referring to as a synchro gear.  

I am not sure what your are talking about when you say the linkage gate.  I did use the linkage arm that came with the 231.  The problem feels like the gears are not lined up correctly or something.  Oh yeah, I know you don't have to remove all of the gears when pulling the input shaft, but my stepfather did anyway.  He won't listen to me and is kind of hard headed.  I have printed out a service manual for the 231 and we are going to open up the case and see if we find anything.  

The shift gate is in the console. It forces you to move the shifter to the side when shifting. When you pull the shifter, it stops, then you have to move it to the side and pull some more. That stop is the gate.

Shift the TC from under the vehicle while running in neutral. Remove the shift arm from the 231 and use vice grips directly on the stud. This will isloate your linkage from the equation.

What input gear did you swap in?

Don't reuse the snap rings, replace them.  

Hello I had this problem w/ my 231, it ended up being a bent shifter fork in the transfercase.  

I think we found the problem, but I was wondering if anyone could confirm it.  We bought this transfer case used through Oreilly's Auto Parts.  When we looked over the parts in the case, I noticed that one part was different from all the other parts I have seen in Service guides and other peoples photos for rebuilding a 231. The difference I notices was that the shift sector was shaped differently then the one in the photos.  The shift sector is the piece that moves the shift forks up and down.  Here are some pics of the one that was in the 231 Tcase I bought.

Here are links to pics of the part I found in the Tcase
http://i140.photobucket.com/albums/r26/kcarrancejie/0810081313.jpg
http://i140.photobucket.com/albums/r26/kcarrancejie/0810081314.jpg
http://i140.photobucket.com/albums/r26/kcarrancejie/0810081403.jpg

Let me know if I am wrong, but I am pretty sure this shift sector was not made for the 231 Tcase.  

Where did you source the input gear that you swapped in? Did you try shifting the TC before you removed it? It is hard to shift it on the bench without the main shaft spinning.

It seems difficult to beleive that the sector would be incorrect. But, I've seen wierd stuff before?? Are you sure it didn't get switched from the 249?  

I am positive I didnt switch this one from the 249. I never removed the one from the 249.  The input shaft came out of my 249 and the gear that slides into that on the first fork came from the 231.  The difference that I noticed from looking at other build guides is that the top of the shift sector that the syncro gear fork runs on is smooth and slightly rounded where as this one has the big crown on it.  Here is the 231 srvice guide
http://www.pirate4x4.com/tech/billavista/PDFs/New%20Jun%202003/Jeep%20component%20service%20manual%20TCase_NP231.pdf
If you look on page 12 you will see the shift sector and see what I am talking about.  

Click here for more info on input gears.  

The input gear is in the planetary. The main shaft holds all the gears and slides down into the input gear after you install the planetary. When you say input shaft, that is confusing. Do you mean the input gear is from the 249? And everything else is from the 231?  

http://i140.photobucket.com/albums/r26/kcarrancejie/IS.jpg
The link will take you to a picture of what I am talking about.  The pic is from someone else who did the swap.  The part in the picture with the long shaft is from the 249.  I swapped it in place of the shorter input shaft.  So it has a 249 Input shaft and the rest is a 231  

Not sure I would have done that. That is the whole low range planetary gear set. The input gear comes out if you remove the snap ring. I don't know if the planetarys are compatible and interchangable.

I would try to not mix anything more than I had to. I would only use the input gear and use the 231 low range planetary gear set.  

This is the swap I was going by.  
http://www.mallcrawlin.com/forum/showthread.php?t=2781
There is also another one that includes pictures.  I can't find it right now, but when I do I will post it up for you.  

The URL you posted also states to swap the input gear, not the whole low range planetary gear set.

Did you read the link that I posted for info about input gears?

There are pictures and descriptions that are in sync with the URL that you posted, which is not what you swaped according to the pictures you posted of the planetary gear set with the input gear still installed in the planetary gear set.