quote:
Originally posted by TooSlick:
GSV,
Read the article in Lubes and Greases again ...
The quoted price difference between Group III and PAO basestocks was $1.50-$2.00/gallon - that's only 35 to 50 cents per quart. A Group III basestock will generally require a more robust additive package to stabilize it, so there really isn't the cost savings everyone thinks there is. Companies like Petro Canada, Chevron and Shell that sell Group III based synthetics for $15.00/gallon all make their own basestocks in-house. They are also selling these products at a fairly low profit margin in order to gain market share. When Castrol switched from PAO to Group III basestocks, they probably only saved about fifty cents per quart on the fully formulated oil.
The data I've seen indicates that a Group III basestock with an OPTIMIZED additive package will perform like a PAO up to perhaps 10,000 miles. The extended drain market will continue to be dominated by the PAO/Ester synthetics.
I recommend the following SAE Paper:
#2000-01-2920
"Formulation Capabilities with API Group III Synthetic Fluids" by Petro Canada.
Part of this paper compares a 5w-30, Group III and 5w-30, PAO based synthetic - using the exact same additive chemistry and VI modifier. The comparison was done in Ford taxicabs w/ 4.6L, V-8 engines. Oil analysis was performed after 7500 mile and 12,000 mile change intervals and engines were torn down and rated for wear and deposits. These results showed essentially equivalent performance from the Group III and PAO based oils in all respects - wear/deposits/oil degradation ....