More information on Group III synthetics:
http://www.chevron.com/products/prod...npra_paper.pdf
An excert:
In addition to the
synthetic moniker, customers are also concerned with performance. Modern Group III base oils perform at a level that is significantly higher than “conventional” base oils, both Group I and Group II, and substantially match existing levels of performance in finished lube applications already established by their traditional
synthetic counterparts.