Re:Weight of Step Van?
Look at the vehicle tag at the door post (?). It will give the max. gross wt and I think the empty wt or max. load. Info varies per each manufacture, but max. gross road weight must be stated.
You can also verify the max. wt by the number of axles, tires, and tire size. The link to those max. legal road weights is posted in another tread. Use the search to find.