Originally Posted By: DWC28
Several years ago Castrol sued Pennzoil over maximum protection against viscosity breakdown. In that case the court found that high temperature, high shear viscosity (HTHS) was more important than shear stability.
Comically enough, that lawsuit centred around the claim "outperforms any leading motor oil against viscosity breakdown".
http://www.leagle.com/decision/19921223799FSupp424_11161.xml/CASTROL%20INC.%20v.%20PENNZOIL%20CO.
Castrol states:
Originally Posted By: Castrol
8. In a series of five television commercials, and in other media, Pennzoil makes the following representation about its products: `Pennzoil outperforms any leading motor oil against viscosity breakdown.' This claim of product superiority is false on its face. When compared to Castrol motor oils, Pennzoil's motor oils do not provide superior protection against viscosity breakdown. Castrol motor oils equal or exceed Pennzoil's products according to every industry standard of viscosity breakdown. In fact, in industry approved laboratory tests, two of Pennzoil's three leading brands of motor oil failed even to pass the most demanding test of viscosity breakdown protection.
9. In addition, Pennzoil's television commercials convey the false and misleading message that, because of Pennzoil's purported viscosity breakdown advantage, Pennzoil motor oils prevent `engine failure' better than other motor oils and afford customers `longer engine life' and `better engine protection' than other motor oils. These claims are baseless. There is no proof that consumers run any risk of suffering engine failure or shorter engine life if they use a motor oil other than Pennzoil.
10. Pennzoil's television commercials are false, misleading and deceptive, in violation of federal and New Jersey law. Castrol seeks an injunction prohibiting defendants from broadcasting the Pennzoil television commercials at issue or from making similar claims in any medium.
Pennzoil's response:
Quote:
In support of its contentions, Pennzoil relies on an industry recognized test referred to as ASTM D-3945.1 This test measures viscosity breakdown and its results are reported in terms of percent viscosity loss. Because Pennzoil motor oils report a lesser percent of viscosity loss than other major motor oils, it reasons that its media statements are true and do not violate the Lanham Act.
With regard to Pennzoil's engine wear and engine protection claims of superiority, Pennzoil asserts that less permanent viscosity breakdown and its exclusive use of the "star" polymer provide greater protection against engine wear.
And now, Castrol claims for their own products "Maximum protection against viscosity and thermal breakdown"
http://www.castrol.com/en_us/united-states/products/car/motor-oils/gtx-product-page.html