Hi, eventually took car to workshop and mechanic came for a drive. He recognised the noise right away and put it up on a lift to show me where the problem is. It's part nmber 8 identified in the diagram. Part ordered booked in for next week. Will update asap
Noise gone, invoice says replaced trailing arm. I asked mechanic to replace reverse light switch while they were working on car. Reversing lights were sticking on. parts plus two hours labour total was arround 430 pounds or $700.
This has to be the same problem that I am having. Brought it in for repair with 120,000 servicing and they did not find cause, of course probably did not look very hard.
Thank you for sharing this news. Will have trailing arm checked..
I had similar noise I think. It was perfectly described on one forum (which I can't remember) as the sound of pool balls being emptied from a pool table. If it does turn out to be the part you identified then you may have to budget for all the other one on the other side and the similar front two. I assume they have similar service lives as my other side started making a noise a couple of weeks after the first. A month later I got a similar noise from the NSF and now I have the OSF on order! I happened to notice today there is an article in '911 and Porsche' magazine about replacing the bushes with poly ones. I didn't read it all as I just flicked through it on book stand but maybe this is a better/cheaper solution than replacing the whole arms with Porsche OE.