scott! hey fellow richmonder. i live here in richmond as well. i just asked my mechanic when my 85 300TDT was in about switching to synthetic, he vehemently dissuaded me from doing that. he said it would leak a lot more often and rattled off about 10 other reasons not to switch to synthetic. he said if the car were newer, like post '95 i should think about it, but not the w123 diesels.
send me an email sometime -
estarr@starmail.com
maybe we can get together and chat if you want
eric