Hello, Finally got myself a BMW. X120d XDrive 2018 - Auto with 56k miles and full BMW service history. However, after 1 day, it came up with a Drivetrain Fault. The dealer has taken it to a BMW specialist, who has diagnosed a gearbox issue and booked it in with a gearbox specialist next week. Under warranty, so no cost to me. At the same time, when I turned the engine off, there was a loud buzzing from the engine, like something was trying to run but was stuck. They have told me this is linked to the gearbox issues, but that doesn't sit right with me. Can anyone confirm or offer any advice? Thank you