Hi Ashby

I am glad to hear that you are not quitting the wheeling... As for the vibration, I am not sure it's related to anything you mentioned:

1. My pahnard rod is also very long. My current suspension setup gives me huge flex. But I have no vibrations under any condition.

2. The rear driveshaft on my Rodeo also made a deep depression/cut into the gas tank skid plate, but I never noticed when and how this happened. No vibration.

Ahsby, may be something shifted in your rear suspension and it must be re-aligned (although I have no idea how the rear alignment can be done). Other than that, I have no idea.