Benzer0matic

Hi guys, I'm new to MB's. Coming from M42 BMW for the last 13 years and now switching over to a 08' e350 4matic there is quite a difference (although I'll never sell my M42)! I am loving this car more and more everyday I drive it, especially in the snow, LOL! Is there anything I should be be aware of while its still under warranty? I hear a knocking sound from inside the cabin once the car is warm, any ideas? It sound louder than normal to me especially since I have been the only mechanic for my older/beater car...I have only 33,670 miles on the clock and also added 1qt mobil1 0w-40 to it since I bought it with 32,500 miles on the odometer...what say you??? Is this sound normal with routine maintanance recorded?

Steven M.