Noise and Vibration comes and goes while driving?

[petesman]

I have owned by 280sl for 15 years and this has never happened before.  Car is responding fine----and then it starts vibrating and making almost like a "rubbing noise"----and disappears?  This cannot be good.  Any help would be appreciated.----peter

[Cees Klumper]

I would look at the driveshaft bearings and universal joints. And the differential mounts. Don't drive the car until you have found and corrected the issue.

[Mike Hughes]

Check the rubber rotoflex coupling between the transmission and the driveshaft.  The rubber will perish over time.  Not fun if it lets go!