I have only a weight distribution hitch on my FF-189 and have never had a problem with sway. I pull with a relatively heavy truck (chevy pickup) which may help. That includes a crosswind in Georgia strong enough to bend a kayak rack almost dumping my most prized posession on I-95
2009 FF X-189 FDS
2011 Chevrolet Z-71 LTZ 4X4 p/u.
Reese WD hitch
Patient and understanding wife