Kuan has just offered a GREAT piece of wisdom. CLEAN oil is best!
The German oil suggestion is a new one on me.
There is one question that I would ask before recommending oil; is your engine gas or diesel? If gas, you have more choices, but Mobil One is certainly at the top of the list. If it is diesel, you should use a Universal grade oil that is formulated specifically for diesels. It has more cleaning agents, particularly for the purpose of soot dispersal.
The original engine in my 240D went 380,000 miles on Chevron Delo 15W40, a universal grade oil for diesels. I doubt that a German oil would have taken it any further. Maybe more importantly is the fact that the oil never went over 3,000 miles without being changed. As Kuan said, "clean".
Change oil hot and change oil often,