[928uk] ATF leak

[Simon Kirk]

Hi all, 
I am about to try and stop a leak from the auto box on my 1989 S4. I have replaced the sump gasket but the leak is still there and seems to be coming from above the reservoir area. A bit of internet searching seems to point to the Bowden cable o ring. Has anybody been in a similar situation and can anybody confirm the part number of this o ring. I am thinking that there will be a cheaper part number from Mercedes as it is an MB auto box. Any helpful advice would be greatly appreciated.

Simon
1989 S4 auto
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