It DOES use an additive package ... it just uses an elongating chain to provide the multi-viscosity. It still has moly, zinc, etc. additives to act as wear additives. Long term lab testing shows that they are expended in the oil over time.
I know they use anti-wear additives (and additives to keep your gaskets and seals soft longer, and detergents...), but I was referring to viscosity modifiers to make it multigrade.
I think their long changes is due to their service plans giving away oil changes, well... to some degree. The oil itself will go that long, with regular filter changes. The key is the filter change interval.
Yeah, to a large degree it is that. That and most Euro customers just hate taking their car in for repair. What's supposed to be 15K turns into 20+ in a hurry...
I wonder if the fact that my car holds 9 quarts of oil has anything to do with it, lol....
Increased capacity is mostly for the increased cooling that it imparts, hence the air cooled engine carrying 10 quarts - they're actually oil-cooled. More oil = cooler oil. It will help affect the lifespan of the oil to a degree, but the overstressed nature of most modern Euro engines will offset that small side benefit.