Heavier WD Bars Or Different Sway Control

I've towed the TT in my sig with the same setup. I think your tongue weight is probably a little light. A trip to a 'Cat Scale' would provide you with figures to start with. Have you checked your light/heavy height measurement on your truck? One other side would be are you towing on P'Metric tires? If so a change over to a LT Tire would help-you firm up your tow vehicle.

I tow with the same hitch setup as yours and I was light on my bars. I went with the proper weight bars and my sway problem disappeared. High-winds are another matter altogether slow down till manageable or stay parked in a safe spot.