Am i doing something wrong? Is my extendable gooseneck tongue down too far and has too much play? Its a bulldog 20k 4" square coupler, its upgraded over the 12k one or whatever was standard. The trailer is a down 2 earth 32' 14k with i think 8" channel beam and 10" channel beam up front and 8" behind the tires. Its around 5200-5700lbs empty, "guessing". When its empty it rides ok, but not much tongue weight for the bed of the dually F350. When i put anything of weight on it, 5000lbs of salt on skids or tractor or 2 cars etc.... when i take off, you feel it jolt, like something is lose. I swore after i got it, i had to check the ball 9times because i thought it was lose. When you hit the brakes, it bucks back and forth and almost feels uncontrollable. Ive tried NO trailer brakes, just truck brakes, seems like you feel the first jolt of the trailer flexing closer to the truck but then its smooth. With trailer brakes " a lot", if bucks harder but then evens out fast. With normal braking on the trailer brakes, it bucks back and forth a lot, im assuming the flexing of the trailer stopping more or less than the truck brakes? Its pulled by an 06 f350 diesel, built in brake ford controller like our other trucks. I dont feel anything of this sort with any normal bumper pull trailers, does it need more reinforcement up front or something? Here are some pictures.