So first bad weather today a lil sleet and freezing rain and I of course have an errand to run. So I put ole trusty (2000 xj stock with 231 xcase) in 4wd and i'm on my way. A lil bit down the road the whole thing just goes into neutral and wont disengage back to 2wd. I stop and put it is park then it shifts back to 2wd and drives just fine. So I decide to try again and it goes back in 4wd and drives fine for a few miles and then the same thing happens. I've looked the forum over and maybe a vacuum problem, maybe low on fluid (I've never actually changed the fluid in there because I rarely use it). Any thoughts or whims would be helpful. Thanks.

stock 2000 xj 166000 miles

 

I would start by changing the fluid. Then I would see if adjusting the TC shift linkage fixes the problem. He is a vid on how to adjust the linkage.