Make sure you have a set of E torx sockets on hand because pretty much everything is E torx on the water pump and housing. Whatever water pump you buy make sure it has the large impeller. There are several impeller diameters, just make sure it's at least as large as the one you took out.

You can use any aluminum safe coolant. There's nothing special in the MB cooling system that is incompatible with any cheap green coolant on the market.

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CENSORED due to not family friendly words