R380 Gearbox Input Shaft Question .

With the r380 gearbox and transfer box out of the car I find I can spin the input shaft freely , regardless of whether it's in high or low or neutral , in gear or not . Except once when I was trying the high low selector back and forth I was surprised to see on one occasion that the shaft actually turned the transfer box flanges . Can anyone tell me what's going on with that ?

Should add this to previous post so we get the whole story.