Thanks Len, it's my first benz and even my Porsche has the green stuff I'm still getting used to benz and its long service intervals like 160k for plugs ... woah! The coolant is a brown/amber. How do you tell if it's full, I dont see any marks on the container?Probably both. Mercedes coolant for your car is a light amber color I believe and is due to be serviced every three years. Use only Mercedes coolant or Zerex G05, not any green stuff.