[SCBillandJane]

I also tow with a light duty 4 wheel drive pick up. In the last 6 months we have traveled from the most Northwest point in the US in Alaska to the most Southeast point at Key West, Florida. No sway under any conditions, and only a WDH hitch without sway control. I agree with PopBeaver. You need to check the weights. Another source of sway is using P instead of LT tires or having the wrong air pressure front versus back. Look at the owners manual to see if Ford has a special recommendation on air pressure for a heavily loaded truck. I agree with some other posters that solving the problem without sway control is best. If you have something causing sway with a Trailmanor then a sway control will hide the problem and which can turn around and bite you. After finding the problem, adding sway control as extra insurance is a choice.