In article >,
Scott Dorsey > wrote:
> If you look at the "Castrol Syntec" line, for instance, you will see
> that all of the different viscosities are actually totally different
> formulations. The 5W-40 meets the current BMW specs and is a "true
> synthetic" oil by European standards... the 5W-50 has a different base
> oil and could not be sold as a synthetic in Europe although it's
> considered a synthetic oil by the FTC here in America.

> Unfortunately something similar happens even with the low-cost GTX line
> of oils.... different service specifications at the different
> viscosities, and then they sell some other variants like "GTX High
> Mileage Oil" which in fact are almost completely unrelated and have a
> very different additive package to them.

It's often a problem where a maker uses the same name for many years. The
spec changes dramatically, and the older spec is often sold at the same
time as the latest. Mobil 1 is the same in the UK. Of course if you
understand the codes you can tell which is which. But perhaps it should
have a release date for that particular version on it.

--
*It is wrong to ever split an infinitive *

Dave Plowman London SW
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