For the last two posters, don't forget there are more and more of the torsion type axles used on tandems and there the manufacturer even warns about towing in a nose up or down (i.e. "NON LEVEL ATTITUDE") causing undesirable load distribution between the axles and I feel the same would go for the tires on such a suspension system with different sized diameter tires and a 1/2" delta over only a couple of feet is one heck of difference IMO. I admit with the older style equalizer/spring type the difference might be less, but no one knows really just how much and with TT tires normally already almost at their full load capacity in many cases right from the factory I still say that "will probably" an overloading on the larger diameter tire.
Biggest issue is there is no way to tell just how much damage you might have done until that tire fails and causes a significant amount of damage for lack of $100 to $150 in the cost of a know good new tire.
Larry
