Late to the party but I have to give my input on towing with the Blue OX Sway Pro. 3 years ago, I originally started out with one hooked up to my 35 ft TT. I towed with a Yukon XL Denali for a half dozen local trips; the rig was relatively stable with very minimal sway. Come mid summer, I was towing the camper home in a"wind storm" with 35-40 mph cross winds. Scariest drive ever for my wife and I. Didn't know if it was the 1/2 ton chassis I was towing with or the failure of the Blue Ox in threatening conditions.
So, I did my research and wanted to eliminate sway all together. It was either going to cost me a new HD truck or a new hitch. I chose the cheaper route with the purchase of a Hensley Arrow. The HA was the complete solution to my control issues. Not an a trace of sway in any condition. Unfortunately, the heavier Hensley put me a tad over on my payload and I knew an upgrade in TV was in order soon.
Six months later, I found my current truck, a 2017 RAM 2500 Megacab 6.4L. It offered me all the payload reserve in the world pulling my 7,600 lb TT. Come first trip of the season, I was reluctant to reinstall my Hensley so I installed the Blue Ox instead. Trailer was nice and level, weights were perfect, and it was clear skies ahead on our day of departure.
After getting on the interstate, the same movement I experienced with my Denali/Blue Ox began again. Not as bad, but I was back to looking at my mirrors constantly and making minor steering corrections pretty frequently. My wife could even feel the lateral forces move the trailer independently of the truck. This brought back some bad memories for the both of us.
We completed that trip and had our next a few weeks later. This time, I switched up the hitch to the Hensley Arrow. Now the truck felt like it was one with the trailer again. No lateral movement from passing semi's, hill cresting or crosswinds. The different I could feel over the Yukon was in the RAM's suspension as the ride much more stout. The Denali's rear air suspension was more forgiving over bumps.
This is not a write up for how great my Hensley hitch is. One can do an internet search to validate that. It's a write up on how poorly the Blue Ox performs with longer coaches. I been been on quite a few forums over the years and that seems to be the common denominator with those who have issues with the Blue OX. They have a longer trailer (ie > 33 feet) and after a few trips out, under the right conditions, the sway presents its ugly head and they proceed to write about their concerns.
I conclude with this. If you don't find a solution with your current setup, take a leap of faith on a better hitch. I'd recommend a premium like a Hensley or Propride but I'd also recommend a 4pt Equilizer as everyone I know swears by them. The latter would have been my 2nd choice if I hadn't discovered the Hensley. Good luck and safe travels.