Quote:
Originally Posted by endless_pain
100 percent synthetic only uses base IV and V synthetic base oils while "Full Synthetic" can use as little or less of 10 percent of a IV base mixed with mineral based oils (I, II and III) and still be called "synthetic" thanks to Castrol back in 1999.
|
Where are you finding these guidelines? Again this is marketing. The Castrol "ruling" by the National Advertising Division of the Better Business Bureau made no such guidelines and neither does the API or the SAE.
100% anything base stock oils are rare and I doubt they even exist. Red Line uses PAO's and POE's, Motul uses esters and PAO's in their 300V, etc. Each base stock has its negatives and you overcome the negatives by blending different base stocks.