Geeves - What has your experience been with the Lansing dealer? Give me the good bad and otherwise. When I had my 9-5 I thought they were pretty good, but that was a few years ago. The service tech might have changed jobs by now. I'm really close to buying a 9-3 from them.
These engines are tested for hundreds of thousands, maybe even millions of miles before they're placed in a car for consumer consumption. If the manufacturer says that a certain weight oil is what the car needs, then use that oil. The guys in the R&D department know more about the engine than Big Bob down at the Texaco.
Interesting comparison. Reminds me of an oil additive we had here in the states called MotorKote. The guy that developed it is a chemical engineer and lives here locally. I use it since I used it in my '89 Volvo 740 Turbo. Never burned any oil, great car, sold it with 297,000 miles. Anyway, I digress, he used a very similar bearing demonstration system to what this report used. He just had a 3' levered handle that you could press on to create the pressure so it was much less scientific. But, the fact is, you could use any oil and get the bearing to sieze. Apply MotorKote to the bearing and you could not get it to sieze again. I wonder if Royal Purple is adding a similar additive to MotorKote? Interesting article. Thanks.
The MY 08' now says you can use a 5W 30 and 5W 40 along with the previously approved 0W 30 and 0W 40 oils. I don't think there was a significant change in engine design is the last 5 years though.
One reason I'm guessing is that there are naturally many more 5W 30 oils on the market and some additional 5W 40's in the last few years.
Saab does however state that these oils must meet the GM LL standard which most oils don't.
As stated several times over the years on the board here, the only readily and economically available oils in the US with the GM LL standard are Mobil 1 0W 40 and Castrol Syntec 0W 30 Euro Formula.
The Elfs, Motuls, etc. are available but very hard to find and expensive.
The boutique oils, such as Amsoil, that state they should meet the requirements but don't really shouldn't be considered.
Oh and that article that does the bearing test I believe has not been proven to be effective.