So can you provide any details on the Service Bulletin? A reference number or some details on what part is faulty?
I have a 1992 400e that is also having the EXACT problem with my trans. I have flushed the ATF multiple times, including the converter, no difference.
I love my 400e, but it seems like there is always a little something wrong with it.
Just a few months ago, my engine wiring harness finally went out. Now I am having my PS serviced to fix the leak in the hose. Will have my belt tensioner replaced at the same time too.
Hopefully that will cover the "must do" items, then I can focus on the "want to do" stuff. :-)