Tongue weight
The downward force a conventional trailer puts on the hitch.
Ford's 2026 guides tell you to plan on about 10 percent of the loaded trailer weight as tongue weight. A 8,000-pound trailer is about 800 pounds on the hitch. That 800 pounds is payload, and it loads the rear axle.
Too little tongue weight lets the trailer sway. Too much lifts the front axle and overloads the rear. The hitch receiver has its own tongue rating, which can be lower than what the truck's payload could theoretically hold.