As HEC refers to, when I got my Bush Hog 52" tiller, I set the skid shoes to max depth (maybe 6"). On my hard/dry clay, it chopped up the ground well, but it hammered and banged and jostled like crazy.
On a whim, I stopped, adjusted the skid plates to 2", the shallowest cut, and it cut smooth as silk. Visualize the angle the tines are hitting the dirt at each depth and you can see the cause of the banging.
Simple to me: Make multiple passes with the skid shoes set at 2". Second pass, as the skid shoes sink in the soft previously tilled soil, you are likely at 4", third pass 6", etc. Probably doesn't take any longer than bashing your tiller on one deep pass, but it sure seems easier on the tiller.
My two cents.
ron