Tranny output shaft play

[md21722]

With my car on the lift, in neutral, I rotate my driveshaft back and forth, and I hear a klunk noise. Its not a problem with the driveshaft, as diagnosed by MB dealer shop foreman and my mechanic. Holding the front part of the driveshaft and rotating the rear does not make the klunk, and vice versa. But, rotating the hole shaft klunks.

I've compared this to two other transmissions I've seen at my mechanic. One is good - with 30Kmi on it, from a wrecked 190. Turned the output shaft yoke back and forth and its smooth w/out klunking. One is old, broke tranny (not sure what's wrong). Turned the output shaft yoke back and forth and it makes a klunking type noise (Almost as bad as mine).

So, my question is,

(1) how common is this klunking?

and, (2) what are the drivability problem that can be associated with this? - is it possible to create a vibration in the gas pedal and steering wheel?

Thanks,
Brian