Faces may be red over at Royal Purple after the data backing some of their performance claims was challenged by industry giant BP (British Petroleum). Royal Purple made a number of performance claims about its motor oils in testing against several competitors including BP ‘s Castrol brand. BP questioned the data and commissioned an independent lab to perform the same testing protocols to challenge Royal Purple’s results. Here’s a quote:

BP Lubricants said it hired the independent laboratory Southwest Research Institute, in San Antonio, to analyze power output of gasoline engines with Royal Purple Oil and with BP’s Castrol oil for comparisons. “The results were provided to the challenger’s expert statistician who was not informed of the identity of the candidate oils,” NAD stated. “The challenger’s [BP’s] expert determined a 0.9 percent difference in power between the oils, which did not rise to the level of statistical significance, and is well below the 3 percent claim made by the advertiser.”

SwRI did additional tests to independently determine the differences in fuel economy, emissions data and engine temperature between Royal Purple and Castrol motor oils. According to SwRI, “there was no statistically significant difference between the fuel economy, emissions data or engine temperature between the two candidate oils,” NAD said.

You can read the whole article at Lube Report. As AMSOIL was included as one of the competitor’s in Royal Purple’s testing, we felt it was necessary to point out this story. AMSOIL has been publishing “head to head” testing and “naming names” for 35 years and the veracity of their data has never been challenged.