IMHO, ask 10 folks for their opinion and you'll get 12 opinions...
There is a lot to it a not just any single item that folks tend to touch/mention, as it may have fixed it for them.
Towing is a system of many, many components/sub-systems/knobs/dials/etc. Plus many WD hitch systems that all claim to solve sway (most do, but they have to be both sized correctly and the biggie...adjusted correctly)
Many will talk about stiffening the TV's suspension. From higher class tires, to higher PSI, to springs, to everything to do with the TV's suspension. All kinda sorta okay, but most just end up as band aides and not addressing the root cause(s)
Will leave it to the others to advise what worked for them, but note that there has been many newbies lead into circular cycles without resolution.
My advice is first view//read up and learn what sway is. Then what the components & their dials/knobs do.
Bottom line advice is: that the goal is to have the TV's front axle returned to whatever your OEM's manual says. Some talk about front fender height, others to front axle load weight...etc.
Then that the trailer tongue should be in the 12%-15% of the trailer's total weight when loaded.
Finally, that the trailer tongue should be level or pointed slightly down after the complete setup is dialed in
Some better FYI video's on trailer sway. First two addresses tongue weighting and where the weight should be o the trailer
https://www.youtube.com/watch?v=i2fkOVHAC8Q This one has an adjustable trailer axle location. What they didnot show is, that if the trailer axle was moved rearwards, it would tow better, but would have a heavier tongue weight. Why higher class TV's has higher rear axle GVWR's
https://www.youtube.com/watch?v=w9Dgxe584Sshttps://www.youtube.com/watch?v=GWJ4Iy6ek24 this one talkes about WD hitches
Good luck and post back on how it works out for you
Edit...many will say weight ratings are not that important, but I'm not one of them. Sure you can go over, to even way over, but I'll not ever recommend that.
Just note that all things designed/engineered is for the worst day out there when Mr Murphy crosses your path when you'll need every ounce of safety factor the designers/OEM dialed in...and either you have it spot on or not.
Finally, on this is the drivers experience and knowledge factor. What will you do if/when you encounter that situation? Educate yourself well...
-Ben
Picture of my rig1996 GMC SLT Suburban 3/4 ton K3500/7.4L/4:1/+150Kmiles orig owner...
1980 Chevy Silverado C10/long bed/"BUILT" 5.7L/3:73/1 ton helper springs/+329Kmiles, bought it from dad...
1998 Mazda B2500 (1/2 ton) pickup, 2nd owner...
Praise Dyno Brake equiped and all have "nose bleed" braking!
Previous trucks/offroaders: 40's Jeep restored in mid 60's / 69 DuneBuggy (approx +1K lb: VW pan/200hpCorvair: eng, cam, dual carb'w velocity stacks'n 18" runners, 4spd transaxle) made myself from ground up / 1970 Toyota FJ40 / 1973 K5 Blazer (2dr Tahoe, 1 ton axles front/rear, +255K miles when sold it)...
Sold the boat (looking for another): Trophy with twin 150's...
51 cylinders in household, what's yours?...