whaat is the proper procedure for shifting from 2L - 4H -4L

I recently bought a used a 1991 B350 Dodge 4x4 conversion van. This might sound like a stupid question but its my first true 4x4. When I am shifting between the 4 High and 4 Low and back again I tend to get more gear grinding than I want :mad:. I think this is because I am using the "trial and error" method and it sounds terrible and I feel like I could really be shortening the life span of the 4x4 :sadwavey:. . I feel like this is how it goes. While in 2 H and parked (duh :sarcasm1:) lock the hubs. Then put the transmission into nuetral and shift into 4High. Shift transmission into Drive and drive forward atleast 15 feet or so. Do I need to do that before I can shift into 4L? Then do I put the transmission into neutral again and shift into 4Low. After i get the thing in 4L how do I properly get it into 4High and then again into 2H??? I would love to be able to do this without grinding through it like i did the other day.

With most 4WD systems, you can safely shift from 2H to 4H and back up to a maximum of 60 MPH. To go from 4H to 4L and back, the vehicle has to be stopped and in neutral.