For what it's worth a dump scale says my C20 with BBC & 400TH weighed approx. 4800-4900. I don't remember the exact number, I believe high 4700-4800. Less 340 lbs. in occupants brings it about 4500 dry. Strikes me as low, then again I never fill up the tank, can only guess how how much gas is in there
, and surely it's lost some body weight in favor of self-ventilation & drip.