I mean driveshaft of course; "tranny axle" is norwenglish.

Vibration is only as long as the car runs, but the funny thing is that it may go away after a short stop. When it comes, usually during acc, it stays on and rarely goes away unless you stop the car. And it does not necessarily come on each time I drive, even if I sometimes floor the pedal.

No; I have not yet been under the car, work so far has been on the brakes. Have to get to a place with a lift, because the car is really low under. Am used to the 544, so different in many ways to work on. But I agree with your suggestions, all kind of rubber mounts are suspicious on a car which has been at standstill for years and not particularly well maintained years before that (an economist owned the car for the last 10 years....).

Could a malfunction of the overdrive cause this kind of vibration? I have had a feeling twice today that the vibration is more likely to come if I accelerate with the OD engaged.

Thanks a lot for your tips and your drawing, shall revert when I have found the vibrating gremlin. Will take me a few weeks though, as I will travel next week.

Br, Ola