I am curious if anyone knows what the difference is between the manual transmission used in the F10 550i and F10 M5. Both are ZF s6-53 transmissions. I would imagine that the bolt pattern on the N63 and S63 is the same. However, BMW lists different part numbers for them. The 550i is S6-53-THA9 up to 07/12 and S6-53-THHL (RealOEM.com - Online BMW Parts Catalog) after 07/12 while the M5 transmission is S6-53-HJV (RealOEM.com - Online BMW Parts Catalog). What do the letters at the end mean?