Doug, the reason I ask who you are is that you seem to assume the "Mobil 1 can do no harm" role, ad infinitum. Mobil 1 does an extremely good job in most engines, but there are a few engine types that eat Mobil 1 0W-40 for lunch. Again Doug, where is your data on the new Audi engines? I assume that you have tons of experience with DI engines, do you?
I've experienced issues with M1 in 2 of my recent Audi engines. Other owners have experienced issues with M1 in their recent Audi engines. I have enough analysis data across 22 engines using multiple oils, including M1, to be able to understand what it is doing.
In the RS4 engine, Mobil 1 0W40 Iron wear is off the chart. (M1 seems to have a problem with fuel diluting engines with chain driven camshafts.) Compared to all other oils used in this engine it shows the following traits:
* Poor ring seal, as evidenced by higher nitration numbers
* Higher oxidation
* Extremely high iron wear.
* Poor ZDTP tribofilm retention.
* High consumption following oil breakdown.
The following 502 approved oils flat outperform Mobil 1:
Motul Etech 0W40,and Xcess 5W40
Pennzoil Platinum Euro 5W40
Lubro-Moly Vollsynthese 5W40
By design, RLI 5W40 further outperforms all of these oils.
By training I am Electrical Engineer, and run a consulting business in the design of ultra high performance electronic systems. Some of my oil analysis data is considered good enough, and consistent with lab testing, to be published by Chevron Phillips Chemical and Renewable Lubricants.
Now don't get me wrong, I have absolutely no issue with Mobil 1 in most engines. It does perform quite well. There are just few problem children that will destroy it quickly.