Today I ran across the biggest set of super singles I've ever seen. They're on an articulated off road truck in Homer Alaska. The front cab section of the truck has 2 axles under it. The permanently attached articulating trailer section has 4 axles. All 6 axles are drive axles.
Each axle has 1 tire on each side size 44"X41.00"X20. Goodyear "Smooth Terra Tires"
In short the tires are 44 inches wide, 41 inches tall, and on 20 inch wheels
I took several pictures but so for I am unable to post them.