Battery died and was charged, noticed the car sometimes doesn't shift gears. Mercedes C240, could it be the battery?
The battery has nothing to do with the car shifting gears, that is the transmission that is giving you some issues. Have it looked at by a local mechanic that specializes in Transmissions.
Search Mercedes-Benz C-Class Questions
Are you a UK consumer? CarGurus now has a discussion forum in the UK.
Mercedes-Benz C-Class Experts