1000 pound tongue weight: 1/2 ton or 3/4 ton???

My son has a 2015 F150 XLT 3.5 Ecoboost crewcab, I have a 2011 F250 6.7 diesel Lariat crewcab. I really like his F150, it's really fast out of the hole, gets really good gas mileage, but when it comes to pulling I would not put my 30 foot Work and Play toy hauling 10,000 Lb.(empty) trailer on his F150. Just look at the rating of the tires alone, my tires are rated as load rage 123 (3415Lbs,). My hitch is a class 5, his is a class 3.