go to a truck stop that has a CAT scale. A CAT has individual pads for each set of trucks axles. I'd do it during the night when they aren't busy, explain to them what you want to do and they should be able to assist. Drop your trlr and get an empty weight of your vehicle splitting your front and rear wheels to individual pads. Get a weight. Then reconnect your trlr doing the same setup, but with your trlr axle(s), steer tires, and drive tires on separate pads and weight again. You'll now know the weights, including how much weight the hitch transfers weight off your steers and onto the drives giving you the exact weight of how much weight is on your hitch (drive axle). Cat weighing is usually $8 to12 for 1st weight, reweighs are less.