[Holyterror]

Mobil 1 is the best oil you will find off the shelf, unless you happen to have an Amsoil dealer around. As with everything else, Wal-Mart buys tons of it; you can sometimes find 5 quart containers there for ~$15 U.S. [caveat]This is the only time I advise putting something from Wal-Mart in your car.[/caveat] I used Syntec for a couple years. It's on the list of Porsche-approved synthetics. And, IMHO, it's a terrific (albeit slightly expensive) engine flush.

I have friends at the drag strip who swear by Motul, but I have no personal experience with it. Red Line has a good reputation too, but I can't confirm this either. I've actually heard some complaints about Rotella T, but again I haven't actually used it.

I happen to be using Amsoil Series 2000 0W-30 right now, and it's the best oil I've ever used. This stuff is the ultimate as far as mileage is concerned. Oil analysis confirms that it has better detergent properties than Mobil 1 (either that or my engine is miraculously running cleaner these days). Now, it's not an earth-shattering sort of thing. But impressive. It has the longest recommended drain interval of any oil on the market, 35,000 miles. It's more expensive as well, and you'll probably have to order it. There's nothing wrong with Mobil 1. I have several gallons of Mobil 1 gear oil in my garage.

It's worth noting that Amsoil makes other (cheaper) grades of oil, which are also quite good. If you go with Mobil 1, you'll be in good shape as well. I think it's far more important that you go synthetic, than which synthetic you choose.