Well, after what I thought was a stupid thing, I dumped out the green GC and filled up with the new Golden GC. I am no scientist, but your average car guy. I noticed only one major difference between the two. My car would make this humming noise after I turned it off while running the green GC. I was told this this was a secondary coolant pump in my 1.8T GLI circulating the coolant. Well, after the switch, the car does not make that sound. It still runs whisper quiet and very smooth. I am wondering why they changed from green to gold?