At 01:58 AM 4/27/2009, Robert Stewart wrote...
>Castrol Edge
>5W-30
>They claim in their test against Mobil 1 that 8x better due to the
>fact that in their 100 hr test they beat out the Mobil 1 product:

Q: When are the results of a test useless?

A: When they're not given.

Note that there is NO vertical scale on their graph. Note that they
don't specify how much wear was measured, who measured it, or the
accuracy of those measurements. Also note that they do NOT claim
superiority over Mobil1 Extended, Valvoline Synpower, or Royal Purple,
but claim "protection that no leading synthetic...can beat." The "8x"
comparison to Mobil1 is meaningless without numbers. If one was 0.1
microns and the other 0.8 microns (the test fail limit is 90 microns),
so what?

It was Castol who was the first to start calling Group III oils (which
are made from crude oil pumped out of the ground) "synthetics."

It was Castrol who changed their "synthetic" oil formulation from PAO
(true synthetic basestock, typically built up from ethylene gas as a
source of hydrocarbons) to use the much cheaper Group III. They did so
without notice and without lowering the price.

So, given Castrol's propensity to deliberately mislead consumers about
its oils, I don't believe much of anything their marketing says.