For those interested, some of the commercial truck rags will show the class 3 thru6 or 7-8 trucks sales by manufacture. I personally have not seen a break out of class 3 dw vs sw. Other than for most years in the past, a sw 25 series being as the gvwr was below 10000 lbs, it was really a DOT hd class 2 truck, or what I call a HD 3/4 ton!
With many of the sw35's being over 10K in gvwr, they do truly fall into the DOT class 3 trucks or 1 tons. Again, not sure you will get or find a break out somewhere.
Marty