WARNING: This page is about a different car, the 2013 BMW 550i GT, 2012 BMW 550i GT, 2011 BMW 550i GT, and 2010 BMW 550i GT. However, it is still accessible from the selected car via links, so may be relevant.
2297311 Screw Minimum set: Mechanical tools MW
NOTE:
Ring bolt for removing and installing the E-machine from the transmission bell housing. [Released]