Shaking/Shuddering while towing trailer

Try taking it for a test tow without the W/D or sway control installed. That trailer's pretty light- your Ody should do up to 350 pounds on the ball just fine. Sway shouldn't be a problem at low speed test drive, but if you're nervous about going without the sway control, make sure tongue weight is correct and keep the speed below fifty.

If you don't get the same shudder, you've narrowed it down to one of two things. Add the two components back one at a time (if you still think them necessary) to determine which is causing the problem.