I'm inclined to go with your view on this Pete.
Part of the problems come about as result of poor signage in my opinion at the scales - is a van considered a "truck" ? (As in "All Trucks Must Enter ...." ... "All Commercial Vehicles over X" would be much clearer) Probably depends on who ya ask - someone driving an 18-wheeler may not consider it to be ..... but a DOT officer or scalemaster may - or may not.
Another part of the problem stems from the definition of
"commercial vehicle" which is generally a state definition, and
"commercial motor vehicle", which is defined by the Feds, and which definition is often adopted by states - and who may, themselves, differentiate between the two.
This is what I do know from my own personal experience of either reading actual text of motor vehicle statutes, or reading publications put out by state DMV's or DOT's, and lastly by direct personal observation.
Virginia: If you are a commercial vehicle and have a GVW of 7500 lbs. or more you are legally required to scale. I found this out by reading a PDF available on the Virginia DOT/BMV website.
Michigan: If you are a commercial vehicle with a GVW of greater than 5000 lbs. (I think) you are required to scale in Michigan. I found this out by reading the actual Michigan statute pertaining to scaling. Having said that, I can say that I have driven by open scalehouses on I-75 in MI probably no less than 40 times (before I was aware of what the law actually said) and have never been chased down - along with observing a number of vehicles similar to mine doing the same thing as I drove by. Since I became aware that I was legally required to scale, every MI scalehouse I have passed has been closed.
Iowa: At every scalehouse I have passed in IA the signs have said that only vehicles of 10,000 or more (and maybe placarded ?) are required to enter the scales. Since I don't haul hazmat and I am under 10K I never enter Iowa scales.
Finally, Kentucky: I entered a scale on 75 southbound in Kentucky because I had heard here on EO that vans were required to scale - since that time I have received conflicting information on it. Interestingly, when I scaled that time in KY I was redlighted and required to go up to the scalehouse with my papers. When I entered the scalemaster seemed to be mildly amused that I had entered the scale (my take on it) - he asked to see my registration - and the only thing he was interested in on it was what was my GVW. As soon as he was able to locate that he said "Ok, thanks." Like I said, my take was that he was not really expecting me to scale .... which may say something (or not)
Jeff: Are cargo vans required to log in AL if they are not hauling hazmat ? It is my understanding that if they are not hauling hazmat, there is no logging requirement ?
Richard: What did the sign say in NJ ?