Quote Originally Posted by Jaimecbr900
How do you know that? Why did only Mobil 1 get sued if all the others claim the same and aren't full synthetics?

I'm really curious, not trying to bust anyone's balls about it. Just curious.
Mobil was the first company to file the lawsuit against Castrol. Castol called their Syntec fully synthetic when it was really a Group III & Group IV blend, instead of 100% synthetic polyaphaolefins (PAO's) it was a mix of Group IV POA's and Group III base stocks (crude). Mobil lost the lawsuit against them because the National Advertising Division of the Council of Better Business Bureaus ruled that Castrol could still market its oil as "synthetic" because their mix has similiar properties and qualities of a true Group IV synthetic.

At the time Mobil 1 was one of the few true full synthetics then shortly after they began doing the group III/Group IV mix...but the name and price remained the same. As far as I know Mobil 1 has not made a true Group IV fully synthetic 100% PAO oil in 5 years or more.