My spouse and I are looking at purchasing our first RV, he grew up camping, I did not.... We have a 2019 Chevy Silverado 6.2L with max trailering, manufacturers tow rating of 12,200 pounds and are ...
Im comfortable at 13 with my current setup, in the past when ive had sway issues 15 has helped. 12-15 percent is the normal range and you need to be able to add tongue weight especially with such a long trailer since sway is likely with that 1/2 ton tow vehicle.
also im getting the impression you still think the dry weight is a real number. its not. when you pick your camper up brand new with no gear or anything it will already be well above this published weight.