Just came from the scales on Saturday, had to chime in!
41 feet 7 inch Sierra 365SAQB fifth wheel.
Weight of RV is 14,060 fully loaded and hitched up (pin 2460 )( RV axle 11,600)= the 14,060
My vech is a 2008 Ford F-250 long bed/super crew/6.4 diesel/timbren installed/3:73 gears.
MPG while towing is 10.5 driving 55-60 mph(even when speed limit is 65/70!!
interesting note is with the 26 foot prowler TT we had, I was getting 11 mpg at best. It weighed 7,000 lbs fully loaded! Twice ad much weight, almost same mileage.