Front drive shaft
I have a 95 hijet s110p 4x4 with a 5 speed manual, a high low shifter, and push button 4 wheel drive on the panel. Should the front drive shaft always turn in 2wd high range?
The front drive shaft is always engaged from the transfer case to the front differential regardless of being in 2wd or 4wd. There is a vacuum actuator mounted on either side of the front differential. The function is to basically locks the hubs when its in 4wd. If you are having issues with the vacuum actuators, try replacing the hoses since most often than not it becomes dry and cracked even if they look good. So to answer your question, the drive shaft will be engaged all the time. That's how it's supposed to work.
Am not sure but I think actuator engages or disengages the front drive shaft. If it is so, then it should not turn in 2wd, although it may turn slowly from static friction.