[Got the Bug]

Originally Posted by sparks

Found this article.This study shows that artificially polymer thickened oil (Multi-Grade)
will tend to have a higher temporary viscosity loss (shear) under load
than an oil who's base is the same viscosity (straight weight oil). In
otherwords, multi-grades tend to fail, break down, loose viscosity when
it is needed most... under load, whereas a straight weight oil will not. This sounds like its sayin that multi grade is inferior to strait wght oil ?

http://resources.metapress.com/pdf-p...0&size=largest

Why would Roush, Keith Craft and others recommend multi-viscosity oils for their engines? It might be one of those questions "why ask why??"