Originally Posted By: dave1251
Originally Posted By: FZ1
Originally Posted By: Smokescreen
I can say give comparing same weight conventional vs synthetic that without question that synthetic oil
does not increase fuel economy given operating temperature are relatively warm 10C to 40C, colder temperatures I haven't and probably will not try.
I have been running synthetic for over 100K miles and have recently switched to conventional and there has been no change. Deep down I was really hoping that there would be in favor of syn after all this distance and money...but there just isn't any to be had. Driving style terrain everything being equal (yes, it is true, my commute is that boring and predictable hence I drive a Corolla...and 95% highway so there is little if no variation.
If you fall in the category of relatively warm climate, want to keep your car's engine clean forever..use conventional synthetic will make no difference. Sorry Doog, its just not true. Severe service just shorten the interval...conventionals are pretty much semi-synthetic anyway.
If you have a female drive that sits there idling away, she needs to be educated, or else have the keys taken away.
Not true,for you. That's all that you can,accurately,state. Some of us notice a slight increase in mpg.
The truth is it not verifiable and that goes to at least 1995 when their was a very measurable performance difference between synthetic and conventional compared to today. The study from Ford and Honda engineer's found that grade and FM additives such as moly had a much greater determining factor in MPG performance than synthetic vs conventional.
www.fueleconomy.gov/feg/.../OwnerRelatedFuelEconomyImprovements.pdf.
I am sure a professional that makes their living at studying lubricants and the relationship lubricants has in a IC engine can explain how this makes sense not simply synthetic is "superior" at lubricating.
My point is;a Specific Result is a Specific Result. I agree that newer,higher,oil standards may cause the difference be small to non measureable. Your mpg may vary. Lol.