[rpoz-29]

Anyone here have any experience with Amsoil products? I'm a little curious about their PS fluid, and motor oil.

[Sam Strano]

Personally if I'm running a synthetic, I want a synthetic.....

Things that are "engineered" are still organic bases with a lot of additives in them. Highly refined, yes, but still carbon based.

The whole idea with synthetics is the oil stretches like a plastic bag does when sheered. That's instead of tearing like a paper bag does. Oil works the same way. And I've personally witnessed Mobil 1 filled cars spin bearings when completely topped up with oil. That, among other things that I've seen tells me the bearing film isn't offering protection when you need it.

Frankly, with the standards now, even "junk" oil is fine for normal driving. But I'm not a normal driver, the G's, the sloshing, the high RPM, the heat. If you aren't going to have a problem then any oil, be it Mobil 1, or $.99/quart Mobil junk will be fine. The proof is when something happens like Sean had.

And FWIW, Exxon/Mobil can kiss my ass.

[sgarnett]

Personally if I'm running a synthetic, I want a synthetic.....

Things that are "engineered" are still organic bases with a lot of additives in them. Highly refined, yes, but still carbon based.

To clarify, I'm not certainly not saying that they are all the same, only that I don't have any philosophical qualms about how a good synthetic oil is made if the result is good.

Per the Mobil/Castrol lawsuit, Group III oils can legally be sold as synthetic, but it may be more reasonable to call them highly refined rather than synthetic. I don't have much or any experience with these as far as i know.

Group IV oils (PAOs) are actually synthetic, but the raw material still comes from oil. They may not be the best available, but they are (in my experience) a lot better than "conventional" oils. Mobil One is an example.

Group V oils (the esters) are also organic in origin and made from chains of carbon and hydrogen, just not from "fossil" sources. Whether that is sufficent to call them "hydrocarbons" I do not know. As far as I know, the main "pure" Group V oils are Redline, Motul, and Amsoil.

Most of my "stress testing" of synthetic predated the Group III oils as far as I know, so they were probably Group IV at the time (though at least one is now a Group III). Personally, I suspect that the MAIN problem with Mobil One is that the established specs are wide and Mobil tends to run at the thin end (which is probably what the OEMs want for gas mileage). In other words, you might want to select a thicker nominal grade from M1 to get the same actual viscosity as a thinner nominal grade of some other oil. Is that a marketing problem? Sure. Is it a technical problem? Maybe not, if you select is based on the data sheets instead of by the label (and in fact, I also use the Redline datasheets instead of the labels).

Are the Group Vs better under extreme conditions? Maybe, at least today, and it's cheap insurance for the car I race, so it gets Redline. Given the amount of oil it consumes, and that fact that it has run sythetic all along and should be fairly clean inside except for the carbonized combustion chambers, a Group V is probably also the best choice for keeping it clean.

This post has been edited by sgarnett: Jun 8 2006, 03:11 PM