Every time I add (or take away) something from the van, I get an empty weight ticket. And at the very least, once a quarter, generally the same day that I send in my Quarterly Maintenance Report (best way for me to remember it), I'll get a routine empty weight ticket. If I get loaded with something that doesn't look or feel quite right, I'll make a beeline to a scale, as well.
In my case, my empty weight is currently 6020, which leaves 2530 for cargo. Panther rarely puts more than 2000 pounds on a Sprinter, and the vast majority of my loads are 1000 pounds or less. (In the last 15 months that I've had this van, 62% of my loads have been 500 pounds or less, 88% 1000 pounds or less.) I have had loads of more than 2000 pounds three times, with the heaviest load being 2835 pounds. For me to accept a load of more than 2000 pounds, it will have to depend on the routing and road conditions. I wouldn't want to haul 2500 pounds through the Smokies, but I'd take it for short distances that will be routed over relatively flat land.
No, Sprinters cannot haul the same freight as a Ford 1 ton, because the GVW of a Sprinter is 1000 pounds less than a 1 ton van. Some carriers will try and max out your van every chance they get. Con-Way was like that. Sheesh, every time I'd look up they'd have a load offer of 3500 or 4000 pounds for my E-350, knowing full well that I was contracted for 3000 pounds max. With Panther, I'm contracted for 2000 pounds. Once in a while they'll offer me one that's more than that, and I accept or reject on a case by case basis.
Slow and steady, even in expediting, wins the race - Aesop