They must be using a different oil, I remeber BMW does the same thing. That's why I wanted to know if we can get the oil they're using.
I always use the 3000 miles rule of thumb in changing oil and 5000 for synthetic and have no problem at all in my many previous Hondas and Toyotas. But considering the difficulties to reach the filter and the type of filter Mercedes is using I can understand if they decided to use some sort of oil that extend change intervals