W/D bars for the Dual Cam are different at the point where they attach to the trailer tongue. I have the older Dual Cam system & found that they work best with a considerable amount of tension on the arms. This caused the ride to be quite choppy. Back a few years when most people trailered w/ their car & needed a lot of tension on their W/D bars, the Dual Cam was the Cadillac way to tow. With the bigger/heavier trucks we use now, it just doesn't seem to be that beneficial. (In my opinion).