So how does a full synthetic 0w30 compare in fuel economy and durability to a semi-synthetic 5w20? I have a feeling that Ford Motor compaby chose the 5w20 oil because synthetic oils are banned from being used to meet the CAFE fuel economy requirements. Since its impossible to make a 0w30 petroleum oil that can pass the API tests Ford had no choice but to specify a 5w20 oil. However 0w30 synthetic oils are far superior to 5w20 petroleum oils in terms of fuel economy and durability.
0w30 versus 5w20
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I dont think that using a synthetic oil gives you that much improvment in fuel econmomy. If so the manufactures would make them a factory fill in more models just to get the CAFE credit.
androbot:
I demand a cite for your statement, "synthetic oils are banned from being used to meet the CAFE fuel economy requirements".
I also demand a cite for, "0w30 synthetic oils are far superior to 5w20 petroleum oils in terms of fuel economy" in any application with ambient temperatures in ranges experienced by *YOUR* home state, California.
I demand a cite for your statement, "synthetic oils are banned from being used to meet the CAFE fuel economy requirements".
I also demand a cite for, "0w30 synthetic oils are far superior to 5w20 petroleum oils in terms of fuel economy" in any application with ambient temperatures in ranges experienced by *YOUR* home state, California.
I am probably going to regret this, so I'll keep it very short and simple. In the Fords that I have owned which specified 5W-20, I have noticed an average of an 8% drop in fuel economy when running a full synthetic 0W-30 vs. a semi-syn 5W-20 depending on application. On the other hand, I chose to use the 0W-30 to run much longer OCI's.
With that being said, I have one question . . . do you have any more popcorn surfstar?
With that being said, I have one question . . . do you have any more popcorn surfstar?
During 1976 Mobil 1 introduced a 5w20 fuel economy synthetic engine oil that claimed a 5% improvement in fuel economy over conventional 10w40 engine oils. Most mechanics in 1976 sneered at the oil and dismissed it as snake oil because if it really did save gas the OEMs would use it to meet the CAFE requirements. In 1978 Road and Track reported that OEMs were in fact interested in using synthetic or synthetic blend oils and were proposing a new 7.5w30 specification. The EPA was worried that the OEM's were using synthetic oil as a loophole and that synthetic oil was so expensive that the consumer would never use it and would never benefit from the improved fuel economy so the EPA ruled that no synthetic lubricant could be used to increase fuel economy CAFE ratings. The OEM's instead concentrated on lower viscosity petroleum oil and the mechanics have sneered at synthetic oils improved fuel economy claims ever since. It is true that some OEMs secify the use of synthetic oils but petroleum oil is used during the fuel economy tests.
My fuel mileage was also noticeably worse with 0w30 vs. 0/5w20 in my Civic. But I use full syn both ways, no semi.
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However 0w30 synthetic oils are far superior to 5w20 petroleum oils in terms of fuel economy
Maybe @-35F.
Maybe @-35F.
androbot2084 mate your talking about some aged Data there. It was no doubt accurate for the times even maybe 10 years ago. But now the line between synthetic and dino is a lot closer due to improved additive packs, base oils, and quality of additives themselves. The added protection of synthetic has been negatied for most applications that we use automobiles. Some engines show lower wear on UOA's using dino's vs syn. That being said there are some applications that synthetic would be preferable. I.E. -10 degree F winter's.
Gary Allan glad to see that we agree.
I need one of them little popcorn munchers.
Think viscosity at 100°C. That's all I'll say.
Think viscosity at 100°C. That's all I'll say.
Assuming that manufacturers have to use dino in their EPA testing, does anyone have specific knowledge if that applies to Corvettes that come with M1 5/30 factory fill. Seems like that might make the difference between guzzler tax or not.
androbot,
Let me start off by saying that I appreciate your actually responding when I demanded a cite. Most guys on here don't.
I will, however, note that you did not link to a web site operated by any respected person, business, university or organization, nor did you cite any printed text. In essence, you cited nothing.
Let me start off by saying that I appreciate your actually responding when I demanded a cite. Most guys on here don't.
I will, however, note that you did not link to a web site operated by any respected person, business, university or organization, nor did you cite any printed text. In essence, you cited nothing.
Saying "far superior" in the original post sure affected the whole thread!
I think that 0-30 and 5-20 oils are very good and comparable in most respects. Certainly within 'spittin' distance.
I think that 0-30 and 5-20 oils are very good and comparable in most respects. Certainly within 'spittin' distance.
Based on the charts on page 4 of this PDF:
http://www.iea.org/Textbase/work/2005/EnerEffTyre/calwell2.pdf
I'd say that oddball's numbers are more believable if he has a lot of city traffic driving on a cold engine, and less so if he drives long, straight highway drives with no traffic.
http://www.iea.org/Textbase/work/2005/EnerEffTyre/calwell2.pdf
I'd say that oddball's numbers are more believable if he has a lot of city traffic driving on a cold engine, and less so if he drives long, straight highway drives with no traffic.
According to Castrol there is no significant increase in gas milege with 0w30 over a 5w20 at least in the short term. But a synthetic 0w30 can give you a radical increase in gas milege over a petroleum oil for the extended drain. According to castrol a synthetic 0w30 increases its viscosity 13% over 12,000 miles but a petroleum oil increases its viscosity by 55%.
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