Originally Posted By: sammy
Thus is why I thought asking the question for a list of group 4 oils at a website that should be an oil information only website would easily fill my request. "I don't know" is something you don't hear enough in America. I don't care about anybody's opinions, either list group 4 oils or go away. Currently we have two I gather, Redline and Amsoil.
First off, you're not going to get a reliable list of Group IV oils, for a variety of reasons. Oil companies change formulations all the time and don't divulge formulation, let alone changes in formulation. Also, oils are mixtures. There is no such thing as a pure Group IV oil, unless you go to XOM and buy a pure base stock with no additives. I'm assuming that's not what you want.
With respect to your list of Amsoil and Red Line being Group IV, that's wrong and wrong. The high end Amsoil stuff is predominantly Group IV, but questions linger about their API certified oils. Red Line is predominantly Group V. Royal Purple is predominantly Group IV, with some Group V in their old SL line, their HPS line, and their racing line. Group III is used for solubility - this is common across most Group IV oils. GC is another predominantly Group IV oil, along with M1 0w-40, M1 15w-50, and Mobil Delvac 1, and possibly M1 racing oils.
If you want a list of Group IV synthetics, your only reasonable recourse is to go to Germany and buy your oil, or order it from Germany. Their labelling rules with respect to synthetics are strict in that way. Even buying the corresponding North American product of a German Group IV is no guarantee, since oil companies are under no obligation to provide the same formulation across borders. Heck, SuperTech oil can be different in different states.
Also, Group IV isn't a guarantee of engine longevity. I've run many engines for many millions of miles solely on Group I and Group II oils over very long OCIs. There are also Group IV oils (including some I listed above) that are absolutely inappropriate to use in certain engines and don't meet manufacturers' specifications for various engines, or the appropriate API/ILSAC or ACEA specifications. I wouldn't run RP 5w-20, Group IV or not, in a TDI, particularly for a full OCI. I wouldn't be running M1 15w-50 in something specifying 0w-20, particularly if it were being used just as a daily driver. And, I wouldn't run Mobil Delvac 1 ESP 5w-40 in, say, a Mitsubishi engine that calls for older CD specifications only.
If you don't care about people's "opinions" and just want a list of Group IV oils, you're totally out of luck. Unless we get the chief chemists of every oil company on here divulging proprietary group content information or you do what Tom stated and run a very expensive test on every oil in the market or you go and buy pure Group IV base stock with no additives, you're going to only get opinions. Mine are based on things like pour point, flash point, NOACK, marketing, and whether or not specifications of an oil are the same in Germany as they are here. None of these provide for an absolutely certain conclusion; they are only indicators.
Any of these can be wrong. Some of the new Group III+ have some very stellar specifications when it comes to PP, FP, and NOACK. Marketing can be wrong - QS has indicated Defy is synthetic, but with a PP of -30, I call bollocks, since even 10w-30 conventionals can beat that.
Take from this thread what you will. No one knows the group content of every oil. Some people know for certain the group content of certain oils, but they're not talking.