I've.used green coolant in my Volvo 5 banger engines with no corrosion. One Volvo had 400k miles. There much be another connection between the corrosion

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1993 e300
1995 e320
1994 e320
2006 s500 4matic
2004 Jeep wj overland
2001 Ducati 748
2004 Honda shadow aero