Originally Posted by Mad_Hatter
Originally Posted by paoester
Today,
German engine oil performance specs demand the best oils,
resulting in typically longer oil change intervals as well as better engine protection for hard driving.
Show me the data that supports this claim..
German oil specs are well known. The key to understanding it is to look at the tests performed, the amount of tests performed, the length of them, etc. Ringlands must stay clear, wear, longevity, etc.
My VW 508 application says 10,000 mile oil change intervals due to all this. GM's dexos1 intervals are about 7,500 miles by comparison, perfectly in line with how stringent the specs are.
Kia lets you go around 6,000 miles typically in their engines, and allows conventional SN oil. See the pattern here? Let the engineers at these companies bring "the data" as you whine about.
https://www.aftonchemical.com/Afton/media/PdfFiles/Afton-Chemical-Spec-Handbook-September-2019.pdf
Read that, see some tests performed, then get back with us about what you've learned.
Until then, don't try to second guess Mercedes, BMW, VW, Audi, & Porsche engineers.