Hello, I've got 2003 745i with 70k miles and it has some problems with transmission. first one hard downshift from fifth to fourth gear, every time, sometimes strong, sometimes just little bit. Also sometimes it changes gears not so smooth. Another noticeable problem is, when I'm driving fast and suddenly stop the car, it's like something under the car from rear side hits and there's clunk and it seems like I've got rear ended, but this happens not while shifting gears and I think it may be guibo joint fault. I have checked transmission oil level and it was ok and there are no any tranny errors, some say it's mechatronic problem but no one can tell me for sure. Did anyone had issues like this and how to fix it?