The Dempsters I remember had walking beam axles with a double knuckle drive shaft going out to a disengagible hub on one wheel.  I don't recall ever having a problem with them going out of gear once you put them in. 

We're a world away from Hesston, but still not nearly as rough as parts of Kentucky.  The chassis on our B & B I pull spreader has required some welding.  I do not think it was built to be pulled by a track tractor while loaded to about 150% of it's capacity.  Most around this area use trucks, the pull spreader is sort of unusual.  We rented a Chandler last spring and I had a considerably stronger chassis then the B & B I which did not exhibit much welding...had been a customer loaner type machine so I'm sure it got some abuse, and it had 3 12" boards around the top to increase capacity.

If you drove to Hesston from home you most likely passed near us.  Need to get a mapdot back in my signature, we're just about in Missouri and one row of counties up from OK.