If I'm trying to find a 231 transfer case in a salvage yard, how can I tell if it's a 231 (what I'm wanting to swap into my GC) or some other transfer case? Also, if I do find one and can swap it into my Jeep, what will I have to do to install a way to go from 2H to 4H or 4L?? My current setup simply has 4H-N-4L. Any help would be greatly appreciated.

 

a 231 has all part time 2wd 4hi n 4lo. also u can crawl under and look at the the tag on the back side

 

There is a round silver and red tag on the transfercase.

 

This. Here is my current t-case for example.

 

If for some reason the tag is gone the shape is pretty distinctive. There is also a shift lever behind the front DS yoke that you can poke it to confirm things. It will shift into 4 positions matching 2H 4H N 4L.