I had that in my E34 TDS, it turned out to be the clutch itself on its way out, but it manifested itself more as a shudder in the pedal itself, if it feels like its coming from the prop then it more than likely is the centre bearing or where its bolting onto the box.

HTH,

Ben

This is apparently quite common on E36's; happened in both of mine. My first E36 did this really badly when hot in particular, say after a long drive followed by start/stop city driving. My second E36 did this as well though, thankfully, to a much lesser degree.

If your car does this a badly as my first one did, i feel for you; it's a real pain in the neck - it almost felt like the prop-shaft was coming off some times!

I actually bought both the prop-shaft center bearing and guibo (edit: flex-disc) but neither of these were actually the cause, in my case.

The non-asbestos friction-plates in the clutches often cause this. You can replace these, of course but the problem is liable to return, especially if using genuine BMW parts. May be worth trying non-OEM parts.

Good luck.