Kento

Egads...that sure was a long-winded dissertation on the how/what/why of oil viscosities. Interesting reading nonetheless. I don't recall him ever covering the differences in various synthetic grades, and how that can affect not only viscosity, but also long term use, catylytic converter suitability, detergent characteristics, blah blah blah.

adam c

iTrader: (2)

That was VERY long. Now the question is: Does he know what he is talking about??

Kento

There is a hell of a lot more to motor oil performance than simply viscosity characteristics...

John Magnuson

I premix a half pint of Astroglide and it works great for me.

DamonB

Which is exactly the reason a lot of us should not bother using synthetic.

John Magnuson

Yeah, I don't think most folks with an FD use it so that they can change their oil less often. That would be a bad idea anyway because of fuel dilution that sometimes occures with the rotary.

The only real reason for using synthetic oil in an FD that I can see if for the superior high temperature resistance. This helps keep oil temps down a little bit and avoid cooking oil deposits onto the superheated turbocharger bearings.

tmiked

I think Mobil has sold us down the river. The original Mobil1 was 100% synthetic. Then Valvoline and others started selling blends at a lower price. I think Mobil1 is now a blend and not on a par with Amsoil and Royal Purple. The "Advanced SuperSyn System contain 50 percent more SuperSyn" means in english "SuperSyn" is the actual synthetic ester based oil and it is now mixed with regular oil the increase Mobil's profits.

I have used Mobil1 since its introduction and am now planning to use one of the genuine synthetics.

tmiked

That is a good reason, but I would rate start up wear as number 1

Kento

Mobil has never used ester base stock due to the extremely high cost of producing it. They have always used (and still do use) PAO (polyalphaolefin) base stocks, a completely different synthetic compound. If they started adding ester base stock, the final product would end up costing more, not less.

The "truth in labeling" court ruling regarding synthetic oils was between Mobil and Castrol, when Castrol started marketing their Syntec oil as a "full synthetic" when it actually had some Group III base stock oils that are basically refined petroleum product with most of the impurities filtered out. In their usual myopic wisdom, the courts ruled that Group III oils could be labeled as full synthetic, even though their base oils were nothing but refined dino oil, opening the flood gates for all the other oil manufacturers to start marketing "full synthetic" oils.

In reality, what is probably happening is that Mobil is simply including more additives, which means that less base oil (usually the most costly component) is in the final product, allowing them to save a few pennies in producing the oil. Does that make it better or worse? Probably both, depending on what aspect of oil performance you're looking at.