So if this is not enough info what else would be needed?
What is the Payload Capacity on the door sticker? This determines how much trailer tongue weight it can handle in addition to the weight of the people and other cargo in the truck. Typically your truck will run out of payload before it runs out of towing capacity. Essentially, the payload is the difference between the GVWR of the truck and what it weighs without cargo. The best way is to actually weigh the truck. It costs about $10 at a CAT scale. http://catscale.com/cat-scale-locator
2013 XLT SuperCrew Short Bed 3.5 Ecoboost 3.55 E-locker, 7100# GVWR, 1607# payload
2010 Fun Finder Xtra XT-245 toy hauler, 6700# loaded with two dirt bikes, and the truck is within all wt. limits