[kelsfine69]

I have a 2011 Acadia. I got a GM letter in the mail saying that they will top up my antifreeze free of charge due to a low coolant level problem. Basically if the coolant gets low and air is entered into the coolant system it will create a greasy sludge that is very next to impossible to remove. I was lucky to catch it in time on a 2000 Sonoma that my son drives. I had a 2002 Grand Prix that the intake gaskets failed due to the coolant eating them. I have had the green stuff in my 1987 Iroc and 69GMC and flushed it every couple years with no issues. I will be flushing my 2007 Duramax soon and the Acadia when its off Warranty. Dexcool in my opinion is a long life antifreeze that creates more problems than the less service it was intended for.