bwalker said:
Mike, reducing viscosities and the higher viscosity indexof synthetics can indeed net some fuel economy increases. The friction thing is BS though.
Friction thing is BS?Some enlightening reading for you.
http://www.carcraft.com/techarticles/15378/
http://www.engineeringtalk.com/news/klu/klu109.html
The following application-related advantages result from the improved properties of synthetic lubricating oils as compared to mineral oils: improved efficiency due to reduced tooth-related friction losses; lower gearing losses due to reduced friction, requiring less energy; oil change intervals three to five times longer than mineral oils operating at the same temperature; and reduced operating temperatures under full load, increasing component life; cooling systems may not be required.
http://www.mr2.com/TEXT/synth_oil.txt
"Film strength" refers to the amount of pressure required to force out a
film of oil from between two pieces of flat metal. The higher the film
strength, the more protection is provided to such parts as piston rings,
timing chain, cams, lifters, and rocker arms...wherever the lubricant is
not under oil-system pressure. Synthetics routinely exhibit a nominal
film strength of well over 3,000 psi, while petroleum oils average
somewhat less than 500 psi. The result is more lubricant protection
between moving parts with synthetics.
You may want to rethink your statement in light of these and numerous other studies done by independant testers.