Originally Posted by JCL

I have never had a problem with Mobil 1 oils. I would be comfortable using them in my BMW.

On the other hand, I won't ever use an Amsoil oil, as the company just smacks of internet hucksterism. Their marketing model stresses pyramid sales strategies over product quality and importantly to me, product validation.

Amsoil products have not historically had API certifications. They try and trick readers by using phrases such as "suitable for applications that call for API xx...." when they should just come out and say they don't meet the API specs. They hide behind a wall of secrecy using the phrase "proprietary formulation of additives", which is fine, but to those of us who believe in independent validation, such as API, it just means that they are selling undocumented mystery oil, and they are free to change the formulation any time they like, and not tell their customers. That is just nonsense IMO.

Amsoil has now come out with some lower cost oils that are certified to the API spec. Good for them. Makes their previous complains that they couldn't afford to do it seem silly, since they are doing it for their cheaper oils. However, here is the catch. They advise that these oils can not last for the change intervals recommended by BMW, where as the oils with the 'secret sauce' can go several times the BMW recommendation. BS.

Slick, that Amsoil OE oil (another low price point oil that they sell) would be a really bad idea in a gasoline engine BMW in North America. It is an LL-04 spec. BMW had to issue a technical bulletin years ago advising that they were seeing oil breakdown on LL-04 oils in gasoline engines in North America, due to the fuel quality. IIRC correctly it was an interaction between the ethanol, and the sulphur level, with the additives used in an LL-04 oil. No problem on diesel. But putting that in your vehicle is a huge step backwards from a proper oil. Their internet sales model is hard at work, selling the concept of BMW certifications, when they should know full well the downside of the combination they are selling. They are just hoping their customers aren't well informed. Again, they take a hit on reputation.