My np231 developed a problem. It likes to pop out of 4lo when under load(climbing) idles along just fine but once you give it gas it pops into neutral. I've been told to adjust linkage. How do I adjust it? What positions should the lever on the tc be in for 2hi 4hi n and 4lo

 

Shift linkage adjustment as stated in the cherokee manual:
1 remove shift lever boot or move carpeting aside to access lever
2 position shift lever as far rear as possible and insert 1/8-inch shim between lever and shift gate
3 raise vehicle and support
4 under vehicle loosen shift linkage trunnion lock bolt and make sure the shift rod fits freely in trunnion and shift lever tighten bolt securely
5 lower vehicle remove shim and reinstall any components that where removed
Hope this helps good luck to you

 

It's that simple. On transfer case all the way forward is 4lo?