Our 83 had been running on green when we got it, and was fine, always runs with the needle on the 80c mark (even cooler than mine does) we drained it all out and flushed it a couple times with water and some mb coolant, then I made a good 50/50 mix of mb coolant and filled it, still runs at 80c just like before, except now about 90-95% of the coolant is mb stuff instead of the green, at some point I'm going to really flush it out, but its not urgent.

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'17 Metris(VITO!) - 37k - wifes (OC-41k)
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'13 ML350 Bluetec - 95k - dad's (OC-98k)
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