Yowie, like a basketball?
Did you change your clutch and all because of this vibration, or did it start right after the new one was put in?
I was gonna say your clutch is not slipping properly, if you can describe violent chatter as not proper, but if you changed all that to try and fix it then I am not sure.
An overheated and warped out flywheel can maybe make a clutch chatter.
Here's two wild guesses, maybe it's a damaged spider gear in your diffy or a loose u joint. I can't imagine either of those easing up at speed though, more likely to throw parts all over and just quit.
Did you change your clutch and all because of this vibration, or did it start right after the new one was put in?
I was gonna say your clutch is not slipping properly, if you can describe violent chatter as not proper, but if you changed all that to try and fix it then I am not sure.
An overheated and warped out flywheel can maybe make a clutch chatter.
Here's two wild guesses, maybe it's a damaged spider gear in your diffy or a loose u joint. I can't imagine either of those easing up at speed though, more likely to throw parts all over and just quit.