It recomends that i use Mobil 1 oil in my 2001 C320,,, the dealership in which i purchased the car gives free oil changes, brakes, and batteries for the life that i own the vehicle. But i dont think they use Mobil 1 oil.. Will it make my engine run any different? And will it prematurley age my engine?

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2001 Mercedes-Benz C320 3.2
1991 Mercedes-Benz 300E 3.0