Is your trailer level or a little tongue down? I'm having the same problem with mine. Granted it's twice a heavy. I have two friction sway controls and it still wags it's tail on the interstate. At PDI everything looked fine but the area they set it up on wasn't really all that level. Now when I look at it on a dead level surface it looks a little tongue high. That will definitely contribute to sway. I bought a straight line dual cam and I'm setting it up tomorrow. That way I know it will be right.
Retired Fire Dept Battalion Chief
2016 Ever-Lite 232RBS
2012 F150 FX4 W/Max tow & Ecoboost
Getting old ain't for wimps!!!