Everyone says that SYN oil gives you better milage. Has anyone ever tested this? is it even noticable or only a lab would be able to show the differnce.And yes In theory I know it should give better milage.
Syn oil better milage Proof?
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Never seen it documented. Lots of undocumented anecdotal info out there, that's for sure.
Under normal driving conditions, I've found there to be an improvement of 0.1-0.2 km/L using Fuchs Titan SuperSyn LongLife 5W-30. Then again this is a fuel economy oil, and is advertised as such. But push the engine hard, and you'll barely see any improvement at all.
I have nothing scientific to prove this, I just keep fuel economy records and calculate at every fill up.
I have nothing scientific to prove this, I just keep fuel economy records and calculate at every fill up.
where you are, it probably does because it is thinner than its dino counter part at cold temps. Other than that, probably not. I have calculated mpg in my trucks at every fill up for the last three years and i cannot tell the difference between 15w40 and 5w30. I do drive a lot of highway miles. I believe this would be different if you drove nothing but short trips. I suppose it depends on the vehicle you are driving also. I only get an avg of 18mpg so say 5% is only .9 mpg. If you are avg 35mpg than 5% would be 1.75mpg. You would see an increase of 1.75 if you calculated it every time. Actually you can see about .5mpg but it starts becomming too close to other variables to know really if your getting an increase. Also i just made up 5% just to make my point. Honestly, in my trucks, it dont matter. If i look back over the last three years, my best mileage was with ST 15w40 and Rotella 5w40. My mpg dropped 1.6 mpg when i went from ST 15w40 to ST 10w40. It bounced right back when i went back to regular rotella. It really dont make sence but that is what it was. To be fair, i only had one run on 5w30 to compare the rest of my runs to. This was during a time that i ran my truck almost 70 miles a day and mostly highway. I believe it would have been a little different if it were many short trips during winter.
I don't know how to post a table, but here's a sample from my records running Motorcraft Premium Synthetic Blend 10W-30 on a Ford 4.6L 16V SOHC V8 (tire pressures set to 40 PSI):
- 8.8 Km/L
- 9.3 Km/L
- 9.2 Km/L
- 9.7 Km/L
- 9.0 Km/L
- 9.6 Km/L
- 8.6 Km/L
- 9.0 Km/L
- 8.9 Km/L
- 8.2 Km/L
- 7.9 Km/L
- 8.3 Km/L
- 8.2 Km/L
- 8.2 Km/L
- 8.0 Km/L
- 8.0 Km/L
- 8.7 Km/L
Average: 8.7 Km/L (17 fill ups)
And more recently with Fuchs Titan SuperSyn LongLife 5W-30:
- 9.4 Km/L
- 9.6 Km/L
- 9.6 Km/L
- 9.4 Km/L
- 9.3 Km/L
- 9.3 Km/L
- 9.8 Km/L
- 9.3 Km/L
- 9.0 Km/L
- 9.1 Km/L
- 9.3 Km/L
- 9.0 Km/L
Average: 9.2 Km/L (12 fill ups)
That's a 0.5 Km/L difference between the averages, but to be fair there are 5 more fill ups with MC 10W-30.
- 8.8 Km/L
- 9.3 Km/L
- 9.2 Km/L
- 9.7 Km/L
- 9.0 Km/L
- 9.6 Km/L
- 8.6 Km/L
- 9.0 Km/L
- 8.9 Km/L
- 8.2 Km/L
- 7.9 Km/L
- 8.3 Km/L
- 8.2 Km/L
- 8.2 Km/L
- 8.0 Km/L
- 8.0 Km/L
- 8.7 Km/L
Average: 8.7 Km/L (17 fill ups)
And more recently with Fuchs Titan SuperSyn LongLife 5W-30:
- 9.4 Km/L
- 9.6 Km/L
- 9.6 Km/L
- 9.4 Km/L
- 9.3 Km/L
- 9.3 Km/L
- 9.8 Km/L
- 9.3 Km/L
- 9.0 Km/L
- 9.1 Km/L
- 9.3 Km/L
- 9.0 Km/L
Average: 9.2 Km/L (12 fill ups)
That's a 0.5 Km/L difference between the averages, but to be fair there are 5 more fill ups with MC 10W-30.
imo,getting better mpg is not what syn oil is all about.you "might" get better milage when using a particular syn oil as compared to another dino,but it's probably what was IN the oil that made the difference,and even then just slight.weight is a different matter.(ever tried boxing under water?)
...and flow at a specific temp.check the specs on the two.
To me that is a definative difference. Maybe its not do to the viscosity but rather the difference in oils. Maybe it is the viscosity, but one thing for sure, for whatever the reason is, i would stick with the SuperSyn LongLife 5W-30. Also your numbers are are more consistant with the second run. In the first run you have a low of 7.9 and a high of 9.7, spread of 1.8. The second has a low of 9.0 and high of 9.8, spread of only .8. Much tighter distrubution during the second interval. When trying to make comparisons like this, i usually plot the bell curve and remove the lowest and highest 10% just to rule out any out of family numbers.
I changed over my Subaru Forester to Mobil 1 synthetic in the engine, AT & differential. I kept track of mileage for ~ 2,000+ miles for each test. Mileage improved by 0.34mpg with a SD of o.06. IMO moving to Syn from Dino will never pay for itself in mileage even if you triple your oil change interval from 5K to 15K miles. I'm sure laboratory tests in a closed room will verify the manufactures statements but, driver variability, weather and the amount of air in your tires will overshadow any meaningful increase. Ed
I see the benefit of a longer drain interval, but honestly I would rather change regular quaker state every 4500 miles than mobil 1 every 9k.
It gives me something to do, I don't mind tinkering with cars a bit.
It gives me something to do, I don't mind tinkering with cars a bit.
It is very minimal that one may not even notice!
Audi tested Castrol SLX II (GC 0w-30) vs 15w-40 and got 1.9% mpg gain.
Originally Posted By: priler
it's probably what was IN the oil that made the difference,and even then just slight.weight is a different matter.(ever tried boxing under water?)
Agreed!
Originally Posted By: jstutz
To me that is a definative difference. Maybe its not do to the viscosity but rather the difference in oils. Maybe it is the viscosity, but one thing for sure, for whatever the reason is, i would stick with the SuperSyn LongLife 5W-30. Also your numbers are are more consistant with the second run. In the first run you have a low of 7.9 and a high of 9.7, spread of 1.8. The second has a low of 9.0 and high of 9.8, spread of only .8. Much tighter distrubution during the second interval. When trying to make comparisons like this, i usually plot the bell curve and remove the lowest and highest 10% just to rule out any out of family numbers.
The engine is also rather quiet running this oil. It has no API certification, but is ACEA A3/B4, BMW LL-01 and MB Sheet 229.3/229.5 approved. I plan to stick with this oil, seeing it has yielded some very decent results. Plan on getting a UOA as well, just to see some results on paper.
One really shouldn't mess with perfection, although being a BITOGer, I am very eager to try out M1 0W-40 in this engine as well, running a VOA and UOA on both the M1 and the Fuchs.
it's probably what was IN the oil that made the difference,and even then just slight.weight is a different matter.(ever tried boxing under water?)
Agreed!
Originally Posted By: jstutz
To me that is a definative difference. Maybe its not do to the viscosity but rather the difference in oils. Maybe it is the viscosity, but one thing for sure, for whatever the reason is, i would stick with the SuperSyn LongLife 5W-30. Also your numbers are are more consistant with the second run. In the first run you have a low of 7.9 and a high of 9.7, spread of 1.8. The second has a low of 9.0 and high of 9.8, spread of only .8. Much tighter distrubution during the second interval. When trying to make comparisons like this, i usually plot the bell curve and remove the lowest and highest 10% just to rule out any out of family numbers.
The engine is also rather quiet running this oil. It has no API certification, but is ACEA A3/B4, BMW LL-01 and MB Sheet 229.3/229.5 approved. I plan to stick with this oil, seeing it has yielded some very decent results. Plan on getting a UOA as well, just to see some results on paper.
One really shouldn't mess with perfection, although being a BITOGer, I am very eager to try out M1 0W-40 in this engine as well, running a VOA and UOA on both the M1 and the Fuchs.
The largest effect motor oils have on fuel economy is through viscosity, followed by friction modification. Lower viscosity oils can save a few percent in fuel consumption when measured by industry standard engine tests, regardless of whether the base oil is synthetic or mineral. Friction modifiers will kick in a little more, but the combined effect is rarely more than 3 or 4% compared to 10W-30s or 40s.
Synthetics can play a role in fuel economy in three ways:
1. Synthetics are generally less volatile and have higher VIs than mineral oils, so you can make thinner oils without sacrificing oil consumption, catalyst damage, and HTHS viscosity. In other words, you can make better low viscosity motor oils from synthetic base oils than from mineral base oils.
2. Synthetics are generally more oxidatively stable than mineral oils, so the oil can retain its lower viscosity longer. This means the favorable effect from lower viscosity may last longer and therefore save more fuel over time.
3. Some synthetics utilize polar base oils that can lower friction and improve lubricity. This makes them behave like a friction modifier, although they may compete to some extent with friction modifier additives and therefore not add much.
As for measuring the fuel efficiency, only carefully controlled engines tests such as those used for GF-4 certification are sensitive and repeatable enough to see the small contribution oils provide. The average consumer has far too many variables to reliably measure or even see oil related fuel savings, such as city/highway mix, road conditions, tire pressure, driving style, engine condition, fuel brand and dispensing accuracy, sensor condition, temperature, wind, humidity, etc. I plotted my MPG for 13 years on the same car and same gas, and the results varied from 16 to 29 MPG, with 95% of the data being +-15% from the mean. Imagine trying to see a 2% improvement in a plot that swings that wildly. I have to giggle when I hear people report a 5 or 10% improvement after one tank of gas. Such testimonials are worthless.
Bottom line, you will never know exactly how much gas you are saving from your motor oil, nonetheless the contribution from synthetics, but you can be sure that lower viscosity oils will save some fuel and a good synthetic a little more.
Tom NJ
Synthetics can play a role in fuel economy in three ways:
1. Synthetics are generally less volatile and have higher VIs than mineral oils, so you can make thinner oils without sacrificing oil consumption, catalyst damage, and HTHS viscosity. In other words, you can make better low viscosity motor oils from synthetic base oils than from mineral base oils.
2. Synthetics are generally more oxidatively stable than mineral oils, so the oil can retain its lower viscosity longer. This means the favorable effect from lower viscosity may last longer and therefore save more fuel over time.
3. Some synthetics utilize polar base oils that can lower friction and improve lubricity. This makes them behave like a friction modifier, although they may compete to some extent with friction modifier additives and therefore not add much.
As for measuring the fuel efficiency, only carefully controlled engines tests such as those used for GF-4 certification are sensitive and repeatable enough to see the small contribution oils provide. The average consumer has far too many variables to reliably measure or even see oil related fuel savings, such as city/highway mix, road conditions, tire pressure, driving style, engine condition, fuel brand and dispensing accuracy, sensor condition, temperature, wind, humidity, etc. I plotted my MPG for 13 years on the same car and same gas, and the results varied from 16 to 29 MPG, with 95% of the data being +-15% from the mean. Imagine trying to see a 2% improvement in a plot that swings that wildly. I have to giggle when I hear people report a 5 or 10% improvement after one tank of gas. Such testimonials are worthless.
Bottom line, you will never know exactly how much gas you are saving from your motor oil, nonetheless the contribution from synthetics, but you can be sure that lower viscosity oils will save some fuel and a good synthetic a little more.
Tom NJ
I can't say proof but in my situation the slight increase in milage vs. extra cost at oil change time is pretty much and exact wash. I'm counting on less wear at startup and cleaner internals as my pay-back for spending extra for the synthetic oil. As a bonus I only need to perform 2 changes/year vs. 3 w/dino!
I could not see any gain in MPG in my truck, but I did see noticeable (3+mpg) gain in my motorcycle. I went from 48-52mpg to 52-55mpg. But I also went from 20W-50 dino to 5W-40 Rotella.
Im not sure i understand the 16 to 29 mpg spread. At most in my blazer i get close to a 2 mpg spread unless were traveling or something then it will creap up about 3 to 4 mpg better than an avg. On all my trucks, i have a much much tighter vairation than that. Heck towing an atv trailer with 4 atvs on it i only loose about 4mpg. Maybe different vehicles are more sensitive or something but i guarantee i would see and be able to show a 10% increase. 5% may be getting close to normal variation but 10% i could definately see.
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