some interesting thoughts, thanks.

I do have clutch chatter, but only when using it for the first time in the morning, otherwise not.

The symptoms, that of a jumping or lurching in the drivetrain, only occur with a steady or trailing throttle, never when under power. This is not accompanied by any sort of clutch slip, at least not recognisable as such, which is why I think its more of a damper issue than one of friction.

I plan first to check the clutch plate wear from the outside, then depending on the results, pull the transmission and check the release bearing and fork before I go any further.

Have investigated the two mass flywheel on WIS since first posting and I think, if I can understand the worksheet correctly, it didn't come into production until 1989, which rules out my car. Is that what production breakpoint means, when it is introduced? It doesn't seem to correlate with my engine and VIN numbers, which is a little confusing.

Would be very convenient if it was a flywheel damper, but looks like my 300E doesn't have one. Any other suggestions as to cause would be very welcome.

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1987 300e manual 250,000 km (sold)