Oil Viscosity? What's Best

[Lubrecon]

A Snake: Thanks for looking, I don't have any mixer for that case of oil, so I am glad I don't have to drink any. SJ is the API classification for the GF-2 oils that were the standard until about 6-9 months ago. SL is the newest API designation for the GF-3 spec that was commercialized to replace the GF-2 oil. If you want the differences, let me know.

Bob: What a breath of fresh air, all of that carbon from all of those non-detergents stuck in the cross hatching was about to get to me. It is frustrating when you attempt to present facts, but if we all knew everything what would there be to talk about. I would like to make a comment about your statement on synthetics. Mobil 1 is a PAO, or as you know an SHC(synthesized hydrocarbon) built from ethylene gas. It is really not a synthetic since it is made from a hydrocarbon. Your statement that the proponderance of synthetics are synthesized is correct if you are just talking about the PAO products, but a true synthetic is not synthetized from a hydrocarbon molecule, they are constructed from acids, alcohols, and other chemicals. Di-esters, polyol esters, polyalkylene glycols, silicones, and others have no HC in them. Just a minor point, and I am not trying to one up you, your answers are right on, but to some, we are voices crying in the wilderness.

Cobrashoch: Viscosity has everything to do with it. If your explaination about oil getting into the crosshatch pattern and burning, leaving the carbon to temper the the cylinder walls, the the lower the viscosity, the better that would work. However, that discussion belongs with the old wives tales that you don't like about slippery synthetics. Are you trying to say that the carbon left by the burning of the oil alters the metallurgy of the cylinders? I know I am just a young man, 58, but in all of my days in lubrication, in all my time spect with ASLE, STLE, SAE, and other technical societies, I have never heard of anything like this. Will wonders never cease?? Bob's discussion on the 25,000 mile drain interval was correct, but additionally, the heat to back off came from the auto companies, the oil will perform to those intervals, but who was going to accept the liability. The new zinc reductions are a result of ILSAC and catalyst fouling and do not come from the oil companies as I have said before. In fact, the oil companies are fighting them because of the backward compatibility problem that I have mentioned before and finding something to replace it as an AW and Anti-oxididant. The oil companies do not set the oil change intervals, the auto companies do, and 3,000 miles is crazy and is being upped because of the current oils' capabilities. Bob was right about your comments about 2-cycle oils. And he was right about moly, you just can't keep it in suspension in an engine oil. The oil companies tried that in the 60's and Arco had graphite in the 80's or early 90's, failed badly(marketing). One thing, it made the oil black, and no one wanted to put black oil in their engine.

One size definitely does not fit all, but I can't think of a single reason not to use a PAO(Mobil1) over a mineral oil except for a high consumption engine or leaking engine. Oh yeah, price, but when we spend the bucks on Cobras, engines, and all of the other stuff that goes on or in our engines and cars, what's $2.50-3.00/qt.

Bob, don't tell BinB what ND oils don't have, he is going to use them... as an additive???

Ok guys, you think I stirred the pot earlier, how about this, Castrol Syntec is not a synthetic, it's not even a synthetized hydrocarbon(PAO), like Mobil 1. Guess what it is and you will get the straight skinny on why they can call it a synthetic when it is not. BinB need not enter this contest without some proof...of..of..of something!