Yes it is true that synthetic oil has a much higher flash point than conventional oil and a much lower pour point. However, I don't care what type or brand oil you use, it is going to get dirty at the same rate. Unless you were to increase the oil capacity of these engines, which is already at 2 gallons, the ratio of "dirt" to oil is going to be the same at 3K. So how can one go 10,000 miles without changing the oil, wouldn't it become slury by that point?

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1999 MB SL500 (110,000 mi)
2004 Volvo V70 2.5T (220,000 mi)
2014 Tesla Model S 85 (136,000 mi)
MBCA member