So recently I bought a 1992 Cherokee 4.0 automatic that needed a transfer case rebuild. Instead of trying the rebuild out right I found a used np 231 that was compatible. The guy I bought it from said it engaged 4hi and 4 lo with no issues when it was removed. Well I just got done installing this newer np231 and it goes into 4 hi with no issue but when I try 4 lo it grinds and clunks. Now I'm certainly not a master mechanic nor a 4x4 I'm more along the lines of this is my first 4wd automobile ever and mechanically I just try stuff out.... sometimes it works other times not so much.So with that being said I have actually no clue what's going on inside of this transfer case. Is there internally a reason for 4 hi to work and 4 lo to not work? Perhaps this is just a linkage issue ? Any response from someone who has any knowledge on this will be greatly appreciated.