Mercedes Benz C300 owners have reported 1 problem related to engine grinding noise (under the engine and engine cooling category). The most recently reported issues are listed below.
Gradually as the car is accelerating it makes a terrible grinding noise and shakes also jerks when changing gears, confirmed it is a failed transmission, the car has had all the appropriate maintenance just not at a mb dealer and there is a service bulletin on the transmission just not official recall and mercedes is claiming no responsibility as it was not serviced at mb dealer since 2014. Clearly the service announcement is recognition of a problem.
See
all problems of the 2012 Mercedes Benz C300
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