The most important thing I've learned about towing a trailer is that you need sufficient tongue weight to avoid swaying. Weight distribution bars are to distribute tongue weight, so they don't help if you don't have enough to begin with. I towed a little 12 footer with WD hitch and it swayed all over if I went over 50 mph. Another forum member convinced me to move my batteries from the back to the front and that made the whole difference in how it handled. Really. Night and day. So with my larger 21' trailer I followed the same principle and had absolutely no problems towing it with my little Jeep. Now mind you it is an ultralight 3500 lb trailer so it's within my Jeep's limit, but there was absolutely no sway even at highway speeds. And that was with a Fastaway E2 equalizer hitch. (combination of WD and sway control) So I guess what I'm trying to say is to make sure you have enough weight in the front of your trailer if you want to use a WD hitch or equalizer hitch.