I've had chucking since day one. Installed a Morryde and that help some. Pin is 20% and won't be any heavier. Towed with two different trucks. I currently use a B&W and have used an Andersen rail mount. Absolutely no difference in the with between the hitches or trucks in any combination.
I only get chucking on certain types of rougher roads. I get a slight push pull on bridges. 90% of the time it's fine.
Had a TT before and the towing was horrible. Two trucks, several different WDH's and the jerking never left.
I figure there's gotta be some kind of give and take. Even my 5x10 utlity trailer loaded with 4000 lbs of gravel tugs on the truck.
There's no one size fits all remedy. Everyone's towing with a different trailer with a different truck.