Synthetic oil change frequency?
In 2013 I bought my wife a1999 Mercedes 230SLK with just under 25,000 miles on it. The car now has just over 51,000 miles. It uses synthetic oil. It has been at least 2 years since I have changed the oil because every time I check it the oil on the dipstick is the color and transparency of honey. Do I really need to change synthetic oil per the calendar when there is no sign of contamination?