Mobil flooding the consumer market with PAOs notwithstanding, PAOs are in shorter supply than Group IIIs - and by the nature of their infrasturcture and production expense always will be. However, the same technology used to produce Group IIs is used to produce Group IIIs - essentially the feed stock is just left in the catalytic hydro-cooker longer at higher temperature and pressure. (There's a little more to it than that - but not much.)
I have seen NOTHING official in print that GC uses PAOs. It may, but it may also use Group IIIs for all anyone knows. Castrol is mum on the subject. (Duhh!) What we apparantly DO know about GC is that it's heavily fortified with ester, and THAT may be the key to its alleged sterling qualities.
As to the notion of (presumably) harsher climatic and driving conditions in Europe vis-a-vis North America as evidence of European oils' performance superiority, balderdash. Even in the U.S. we have climatic conditions that match most of the winter conditions and outright exceed the summer conditions of Europe (this just recently concluded summer in Europe being the lone historical exception). The average oils that average Europeans pour into their average automobile engines is no better than what Americans typically use. Get into the high-price automobile category - Mercedes, BMW, Jaguar, passionate Italian screamers, and the situation is different. But the same is true in the U.S. with highly tuned G.M. V-8s and Chrysler V-10s where Mobil 1 is factory and recommended service fill.
For all who insist on European "designer boutique" oils, fine. It's your money. But conventional Group II oils are better than they've ever been and average cars will go just as long on them with factory oil change intervals as they will with the high buck oils*. The VAST majority of cars in junkyards are not there because the engine oil failed. They're there because they were WRECKED.
*Where was the vaunted superiority of high-buck oils in the Mercedes fiasco? Mercedes is paying out ~$23,000,000.00 to owners for damage allegedly sustained to engines because the Mercedes DEALERS were using the wrong oil for these extended-drain applications. Am I the only one on this board that's suspicious that Mercedes' position is just a bit self-serving? After all, Mercedes is picking up the tab on these free routine oil changes - NOT the dealer. (Well, really the owners are - those "free" oil changes during the life of the warranty are factored into the cars' cost.) Why would a Mercedes dealer cut corners, then? Could it be that Mercedes was looking for a scapegoat in a desperate attempt to maintain customer loyalty rather than admitting that expecting 15,000+ miles is just too **** much for ANY oil under AMERICAN driving conditions, and that the company's engineers (who's objections were more likely overridden by the marketing department) screwed up in how the "Flexible Service System" parameters were programmed? I'm not dissing Mercedes per se. I truly admire the marque, but the company has had some undeniable QC issues over the past several years. Their obsession with extended service intervals, presumably from "greens" pressure, hasn't helped. I'm not certain which is worse - Europe's "greens" pressuring auto manufacturers for ever longer oil change intervals, or EPA "CAFE" pressures for thinner viscosity. Seems like entirely different approaches to the same problem and until it's worked out which is better, it's the hapless consumers who'll be stuck with the consequences in most cases.
