Quote:
Incidentally, you won't see any recommendation of GC for GM v8's (and probably other gm vehicles) on Castrol's site. This is because GC does not meet the GM 6094M spec. This is likely the main reason behind the illusion that GC is not american car recommended/friendly.
GM 6094M is a low temperature cP requirement that is a sliding scale based on oil grade. The result of this sliding-scale is that if you labelled GC a 5w30, then it would likely meet the spec, but as a 0w-30, it is too thick at a certain temperature to meet the 0w-30 requirements of the 6094M spec (IIRC).
I'll bet that's why I'm getting answers like.."no way" and "absolutely not" from the technical guys.
