I always use the cheapest green coolant I can get my hands on and distilled water. Never had a problem. I swear every euro manufacturer has its own proprietary fill in the blank color coolant. I've heard the same story with BMW, Volvo and Audi owners. If you don't use the ultra special dealer only coolant your engine will blow up and your children will be born with hooves. I call BS.

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CENSORED due to not family friendly words

Thats right,my thinking all dealers.I don't want their oils,weights,and ect...
They want to sell a new vehicle to you in 5 years or less.I use oil that will pass thru their screens but protects.Same with other stuff.

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1999 w140, quit voting to old, and to old to fight, a god damned veteran, deutschland deutschland uber alles uber alles in der welt

The chemist I know insists there's a big distinction...

G05 or even the new BLue coolant by MB are heavily buffered to stay 7.0 ph. Go put a piece of litmus paper in new green coolant 50/50 mix. It starts out acidic- and turns basic as it reacts to metalic oxides in the system. Hot basic solution is not good for plastic or rubber life. Spent $10 for a gallon of G05 or equivlent.
Your system isn't dry- even by blowing out the heater core, I cannot come close to the 10 liter factory fill volume! I flushed 3X with water to remove the green stuff.

Michael