I attended an MB service clinic, and cornered the MB Zone Rep about the issue of the 722.6 tranny and it's so-called lifetime fill of tranny fluid.
He admitted "were it my own car, I'd change the fluid and filter every 90,000 kilometers."
I changed the C230's fluid and filter at 90K. The dealer charged me $275 for parts and labour.
You Yanks would do it every 55,000 miles.
I'm going to have the E300's done this srping, depsite it being only at about 50,000 kilometers, just 'cause it's been in the car for almost four years.
1998 C230 "Black Betty"