I found a discussion on Load Range in a Forum where the question was: How strong of a tire do I need? was being discussed. Here is some of the discussion:
Below you see what is stamped on my tire sidewall:
Load Range is rated at "H" 4940# single tire That's at max pressure!!
Load Range 4675 Dual tires.
Tread is 5 ply of steel. Good puncture protection with 5 steel treads.
Sidewall is 1 ply of steel. Maybe this is why they ride smoother with only 1 steel side wall.
Am I missing something since your Load Rating info does is not the same as mine. There's not enough plies to be rated an "H" tire???
As you can see the 'Ply" can be very complex and simply looking at the number but not the Load range can be misleading.