So I took about and rebuilt my np231 TC. Everything fits and operates smoothly. However, it doesn't seem to be shifting into 4hi. I'm assuming there are three positions the TC shifts into, those being 2hi, 4hi, and 4lo. The whole setup in general is pretty simple so I'm stumped as to what I dis wrong. Any suggestions are much appreciated.

 

It does shift into the 4hi position, but remains in 2wd.

 

When you installed the shift linkage was the arm attached to the transfercase pointing up or down? You might have installed it upside down. Make sure it's pointing down.

 

That was the problem, Thanks for your help

 

Haha I had done the same thing on mine once and it frustrated the heck out of me. Glad I could help.