Engine Oil Viscosity around the World

[Octopus]

Hi all, I happen to came aross some interesting data on the subject matter, and would like to share with you all. Data was collected for Y2008.

Refer: http://www.instituteofmaterials.com/collection.htm

 

IOM they purchase the engine oil from the market around the world, and do their own testing. Sort of like an independent organisation. We can see the viscosity trend among Asia-pacific, Europe, and North America in the charts below.

 

Asia Pacific

 

Europe

 

North America

 

Notice that in Asia Pacific countries, the engine oil is more spread out. 50 weight account for 23%, 40 weight account for 40%, and 30 weight account for 18%. Nevertheless, still slightly towards thicker side.

 

In Europe countries, the engine oil is mostly 40 weight which account for 67%, and 30 weight 19%. Perhaps this is why most continental cars specify ACEA A3, because of their preference for thicker oil.

 

In North America, the engine oil are mostly at the thinner end, with 20 weight account for 11%, 30 weight account for 52%, 40 and 50 weight account for 26%. Also note that their oil there are very cheap as compared to Asia Pacific and Europe countries.

[Octopus]

The engine oil viscosity data for Y2008 suggest that thinner oil such as 20 weight or 30 weight is not that popular around the world, and more or less related to my thread on "Thinner oil = Better startup Protection?", which I have given the facts that its a myth.

 

In Eurpoe I'm sure the weather is as cold as North America during winter, and yet they prefer 40 weight oil. So I think, the trend towards thinner oil is mostly in North America, where they have strong CAFE regulation, and purpose for thinner oil is only for better fuel economy.

[Ithunk]

okay good information....so wat are u trying to substantiate :)

[Octopus]

Have you wondered how come Europe vehicle they do not use ultra thin oil for their vehicle? Their winter is also very cold, yet not common to find 0w20 or 5w20 oil there. Perhaps thinner oil will compromise on engine protection. Europe countries such as Germany, France, etc do make very good engine, maybe they favour protection over fuel economy.

[Yuan]

Thanks for your sharing.

 

Very informative.

[Trex101]

  On 2/19/2010 at 3:30 AM, Octopus said:

Have you wondered how come Europe vehicle they do not use ultra thin oil for their vehicle? Their winter is also very cold, yet not common to find 0w20 or 5w20 oil there. Perhaps thinner oil will compromise on engine protection. Europe countries such as Germany, France, etc do make very good engine, maybe they favour protection over fuel economy.

 

You should start a thread in BITOG and discuss your theory on "Thinner oil = Better startup Protection Myth", I'm sure the many resident engineer and oil siao can discuss more in depth on your theory.

[Octopus]

The evidence from the chart show that they are a nation of thin oil lovers. Believe are hard to change if the view differ.

[Zyrofillica]

from the website, they stated the oil is purchased by their collectors and tested. it is not an accurate picture of the types of oil preferred by consumers but rather a market survey on the oil available in that region.

[Leepee]

nice statistics.

 

[Trex101]

  On 2/19/2010 at 8:14 AM, Octopus said:

The evidence from the chart show that they are a nation of thin oil lovers. Believe are hard to change if the view differ.

 

But you are discussing about engine oil pump mechanic & theory now, fact is fact, no one can dismiss it and get away with it. I'm sure a lively discussion would ensure, i'm interested too in seeing what's other ppl thought your thought/theory.

[Tigershark1976]

  On 2/19/2010 at 8:43 AM, Zyrofillica said:

from the website, they stated the oil is purchased by their collectors and tested. it is not an accurate picture of the types of oil preferred by consumers but rather a market survey on the oil available in that region.

 

 

just take such statistic with a pinch of salt....

[Octopus]

  On 2/19/2010 at 8:43 AM, Zyrofillica said:

from the website, they stated the oil is purchased by their collectors and tested. it is not an accurate picture of the types of oil preferred by consumers but rather a market survey on the oil available in that region.

 

From the website it did state: "IOM performs continuous, independent monitoring of the physical, chemical, and performance characteristics of engine oils purchased from the retail market throughout the world. Oils are collected on the basis of market trends, market share, population of geographic locations, and consumer interest." Therefore, it should represent what the consumer use/prefer in the particular country of interest.

 

By the way, our local megastore cheap c.lube are also included in their survey, but need to pay to view the results.

[Octopus]

  On 2/19/2010 at 10:57 AM, Trex101 said:

But you are discussing about engine oil pump mechanic & theory now, fact is fact, no one can dismiss it and get away with it. I'm sure a lively discussion would ensure, i'm interested too in seeing what's other ppl thought your thought/theory.

 

So what do you think of the theory? Do you believe it yourself, after I had tried my best to provide supporting facts?

Anyway, the basis of my earlier discussion was only for local context, where we never experience freezing condition. If oil do get so cold that it almost solidify (tar like), then even positive displacement pumps would not be able to pump it.

 

[Octopus]

I think the reason why North America prefer thinner oil is due to Corporate Average Fuel Economy (CAFE)

A comprehensive info on CAFE here:

http://en.wikipedia.org/wiki/Corporate_Average_Fuel_Economy

 

Basically manaufacture of vehicle whom does not meet the required fuel consumption need to pay penality. It is interesting to know that:

"The penalty for failing to meet CAFE standards recently increased from $5.00 to $5.50 per tenth of a mile per gallon for each tenth under the target value times the total volume of those vehicles manufactured for a given model year.

Since 1983, manufacturers have paid more than $500 million in civil penalties. Most European manufacturers regularly pay CAFE civil penalties ranging from less than $1 million to more than $20 million annually. Asian and domestic manufacturers have never paid a civil penalty.

For MY 2002, five passenger car fleets including BMW, DaimlerChrysler import, Fiat, Lotus, and Porsche are projected to fail to meet 27.5 mpg passenger car CAFE standard." Refer: http://www.nhtsa.dot.gov/CARS/rules/CAFE/overview.htm

 

So it may be likely that manufacturer of vehicle in North America will try their best to avoid the penality, hence will specify the thinnest oil available.

Other country such as Europe do not subjected to CAFE penality in their own country, hence are fee to decide which weight oil offer better protection yet do not give problem during their cold winter months.

[Trex101]

  On 2/19/2010 at 12:55 PM, Octopus said:

So what do you think of the theory? Do you believe it yourself, after I had tried my best to provide supporting facts?

Anyway, the basis of my earlier discussion was only for local context, where we never experience freezing condition. If oil do get so cold that it almost solidify (tar like), then even positive displacement pumps would not be able to pump it.

 

Personally i don't believed engine oil pump has a fixed flowrate no matter the fluid viscosity, if it is truth then why did oil pressure increase with thick oil over thin oil? Oil pressure will have to be constant in every viscosity for the flowrate to be constant.

[Zyrofillica]

  On 2/20/2010 at 7:29 AM, Trex101 said:

Personally i don't believed engine oil pump has a fixed flowrate no matter the fluid viscosity, if it is truth then why did oil pressure increase with thick oil over thin oil? Oil pressure will have to be constant in every viscosity for the flowrate to be constant.

 

i agree with this too. i think you shd bring this up in BITOG, more technical guys over there who can enlighten you on the subject or debate on your theory. keep us posted on the findings please~

[Octopus]

  On 2/20/2010 at 7:29 AM, Trex101 said:

Personally i don't believed engine oil pump has a fixed flowrate no matter the fluid viscosity, if it is truth then why did oil pressure increase with thick oil over thin oil? Oil pressure will have to be constant in every viscosity for the flowrate to be constant.

 

I can see you are not mechanical trained, right? Nevermind, allow me to show you some gear pumps characteristic. They are different from the common centrifugal pumps, hence I see you are a bit confuse on this area...

 

I said gear pump will give relatively fixed flowrate no matter the fluid viscosity. Pump capacity is directly proportion to the speed. But if the discharge have restriction which cause outlet pressure to increase, then thinner fluid may not be as efficient as the thicker ones because of internal leak or slip.

You mentioned thicker oil gives higher discharge pressure than thinner ones, you are right. Because when the oil are thinner, there are "internal leak" or "slip". Because the gear pumps need to have some clearance between gears and housing and between gears, hence these clearance will allow the fluid from discharge side to be forced back to the suction side. So overall there will be a lessser discharge pressure (and flow) with thinner oil.

 

Please refer to the link which touch on the viscosity, pressure, and internal leak in a gear pump.

http://www.mehf.com/STLE02pumpeffmodel.pdf

Slide 7 and slide 8 is a very good example of 2 oil having different viscosity when pumped thu gear pump. Oil 1 is like a 40 weight and Oil 2 is like a 20 weight engine oil. It is interesting to see that the thicker oil (Oil 1) actually achieve higher flowrate than the thinner oil (Oil 2) as the pump outlet pressure is increasing.

This may contradict Dr AEHass theory that thinner oil gives less pressure which mean more flowrate, but this chart had show that this is not true. Perhaps this also explain why Europe countries seldom use 20 weight oil.

 

May I refer you to another link showing that thinner fluid may result in lesser efficiency.

http://www.liquiflo.com/v2/files/pdf/Gear_Pump_Basics.pdf

Page 2 show the characteristic of water vs oil when pumped thru gear pump. Noticed that oil which has a higher viscosity than water, the flowrate (black lines) are more constant even with increasing outlet pressure? Unlike the thinner water, flowrate is reduce as the outlet pressure increasing, because of internal leak or slip.

 

To summarise, thicker oil gives higher pressure and higher flowrate (Which is better for engine protection).

Thinner oil gives less pressure and less flowrate due to internal leakage. (Which is better for fuel economy, I think)

Hence the balance approach is best, not too thick and not too thin oil.

Edited February 20, 2010 by Octopus

[Trex101]

Like Zyrofillica & i have said before, you should post this in BITOG. There's more technical trained people there in BITOG that can better discuss your theory, personally i don't think your theory is sound.