"You need a bigger truck :)" :) :) it's the cure for everything: bigger
someone had to say it, gently...
Try to avoid exceeding load ratings: eg max tire load ratings, max axle load ratings, max hitch load ratings.
Tow ratings take into account vehicle performance, cooling capability, as well as safety and are somewhat subjective.
Tag or bumper towed trailers require a minimum of 10% of their weight on the tow ball to handle properly, so eventually you arrive at the tow vehicle's hitch rating. 1200lbs on the hitch = 12,000lbs trailer gross weight.
Old school rule of thumb is a 5th wheel coupled trailer can weigh 2x the pickup's bumper tow trailer capacity.