 Re: 1993 ford econoline winnebago dayvan gross/net vehiclewe
Total capacity (GVWR) is determined by the model. i.e. E150 / E250 / E350. An E150 will have 5 lug wheels, the E250 will have 8 lug wheels and a semi-floating rear end (no hub) an E350 will have 8 lug wheels and a full floating rear end (with hub).
Since this is a Motor Home, it is likely an E350, with either single or dual rear wheels.
There should be a hand written or typewritten tag on the drivers' side door jamb, listing the VIN and GVWR, which would have been affixed by Winnebago. Although these are often hard to read as the ink fades over the years. | 
