A concern nobody has addressed is the stress on the rear of the coach. The standard hitch is attached to the engine cradle and the tongue weight is literally cantilivered off the rear axle sub frame.

Unlike Peter's Smart car carrier that carries the vertical loads on the truss frame and has almost horizontal loading on the lower portion, a heavy tongue load with the standard hitch is going to show up in the form of stress cracks on the rear cap attach points.

A good example is looking at coaches in which a motorcycle has been carried on a hitch mounted motorcycle carrier. The stress cracks can be seen at all rivets and across the top of the cap. Prevost has a 20,000 hitch as Kevin pointed out and if a trailer of heavy tongue and gross weight is to be towed at the very least that hitch should be added.

Ditto what Harry said. Those transmission temps are going to get very high and annual Transynd changes are going to be required to prolong the transmission life.