In the seven years I was in the tire industry, there was a huge selection of 16.5" tires, and by the time I left, it was fading away. There was a point in time, when alot of 1 ton vans and trucks were running the 8.75/9.5-16.5" tire size. Cause at one point in time, that was the standard for really heavy loads. Hence, the 6 lug wheels with the 16.5" wheels.
