BMW announced that from November of this year onward it will start replacing gradually the carbon driveshaft in the M3, the M4 and the M4 Convertible with an M specific high-performance driveshaft made of steel.
This measure deemed necessary from BMW in order to create “the necessary technical basis for meeting statutory emissions requirements”, which translates into making the M3/M4 compatible with a petrol particulate filter (PPF) that will be required to be installed in major markets at a later point in time.
The company says that the newly developed steel driveshaft is designed up to the high standards of the M3/M4 models, leaving their performance and handling qualities unaffected.
This pre-enabling process will happen for production-related reasons and needs to be carried out universally for all versions of the M3/M4, sans the limited M4 CS and M4 GTS special editions.