Well, I'm confused. You don't get wheel hop unless you are feeding a lot of power to the tires. I had an old D-100 that would do the same thing in reverse. My guess is that a chattering clutch is causing the shaking problem.
There are a whole lot of car/trucks that will do that in reverse, most people don`t get on one hard enough for it to show up. If his is doing it even if he`s not getting on it , SOMETHING IS WRONG ------