The NV242 is very sensitive to differences in driveline rotations front to back. Make sure your tire pressures and outside diameters match at all four corners. Even having the tires visibly more worn in the back compared to the front can make a difference. Rotate your tires often. I try to do it every oil change but most times it doesn't happen.
When it binds sometimes you can get it to release by coasting in neutral while monkeying back and forth between 2WD and FT. It doesn't always work though.