Take a look at the "transmission" on an older Snapper Rear engine Riding lawn mower.
Similar concept, but uses a large wheel rather than the sphere. Works very well in low speed application (don't know about a highway vehicle), holds up well, can pull a load no problem, etc etc.
http://www.odref.com/partsimages/Ste...9;STENS-240440
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http://www.sjmparts.com/popup_image....D=6455&image=0
Bottom is Smooth
How did you make that animation?