Depends whether you are in the north or south part of Texas.quote:
Originally posted by 427Z06:
Nope. We're going to beat on this dead horse until it emerges in China. Or would that be Australia? Anyone have a globe handy?
I am tired of everybody saying 20 wt oils exist only for gas mileage
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I'm not familiar with the history of the debate here, nor can I argue the technical merits of such oils, or the push or pull of such oils as they relate to engine designs, but I can add this:
Chevron gave a motor oil presentation to our car club chapter a few years ago, and one of the (base stock) engineers told us that the lighter weight oils were driven by the desire of the car companies (Ford was one mentioned) to improve fuel economy.
The "sole" factor? Perhaps not, but certainly a driving factor.
Chevron gave a motor oil presentation to our car club chapter a few years ago, and one of the (base stock) engineers told us that the lighter weight oils were driven by the desire of the car companies (Ford was one mentioned) to improve fuel economy.
The "sole" factor? Perhaps not, but certainly a driving factor.
I just searched for a bunch of the older dino 5w30 UOAs. Seems to me that about half of them thinned out to a SAE 20 grade at 100C, some with less than 3,000 miles.
So as someone else once said, "the public has been running on essentially 5w20s dinos for almost 2 decades now...in the form of sheared back 5w30 dinos."
So as someone else once said, "the public has been running on essentially 5w20s dinos for almost 2 decades now...in the form of sheared back 5w30 dinos."
What about the Jaguar's 3.0 Duratec V6.
Same engine as the Ford except for the heads.
Jaguar's recommended oil 10w30 (5w30 for cold).
Ford....5w20.
Do the heads and ECU really make that big of a difference?
Same engine as the Ford except for the heads.
Jaguar's recommended oil 10w30 (5w30 for cold).
Ford....5w20.
Do the heads and ECU really make that big of a difference?
Originally posted by 427Z06
Anyway, even if we consider tribological theories and fine laboratory measurements, it doesn't discount the fact that when engines are run with spec-ed oil on a dyno for 300 hours at WOT and full load, the wear differences between base-stocks in fully formulated oils, are for all practical purposes, negligible.
Maybe there is a message here. Instead of looking for wear under WOT steady state conditions, perhaps, other than cold start, most wear is occuring during a wide rpm range of max acceleration. I.E., pedal to the metal and redline in all gears. (Well, depending upon the car that is, I've run out of courage, or road, before getting the Jag past 160mph -still below redline- while in 5th and still had 6th to go.)
Anyway, even if we consider tribological theories and fine laboratory measurements, it doesn't discount the fact that when engines are run with spec-ed oil on a dyno for 300 hours at WOT and full load, the wear differences between base-stocks in fully formulated oils, are for all practical purposes, negligible.
Maybe there is a message here. Instead of looking for wear under WOT steady state conditions, perhaps, other than cold start, most wear is occuring during a wide rpm range of max acceleration. I.E., pedal to the metal and redline in all gears. (Well, depending upon the car that is, I've run out of courage, or road, before getting the Jag past 160mph -still below redline- while in 5th and still had 6th to go.)
Depends on how different they are, and/or if through testing, they find any lubrication deficiencies between the two of them.
Seems to me, if we want to pull theories out of thin air, that one could make the argument that since the U.S. is the more litigious country, the last thing Ford would want is a class action lawsuit filed against them for forcing Americans to use inferior oil, therefore it must be sufficient for the task at hand.
Covered through fleet testing in various climates throughout N.A.
I disagree with this notion. The demand curve for motor vehicle fuel is extremely inelastic both here and in fully developed countries overseas. That means consumption is essentially unaffected for more than a week or so by price changes.
The Euros ostensibly tax fuel to such a monstrous degree to discourage consumption, but in fact it simply gets them a ton more revenue. Congestion and other factors make people buy smaller and/or more efficient vehicles; fuel taxes largely do not.
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Well, think about that a little TallPaul. Governments run on revenue. In Europe you "channel" your citizens in a manner that benefits the state. You merely leave fuel taxes high and simply don't put any insentives (other than their wallets) into the mix for "consumption" ..which should not be confused with "conservation". You then have your business/government make the market conspicously void of lighter weight oils and then make them very expensive. You contour your citizens behavior to the needs of the state.
I hope I made enough sense in that there to inspire some sparks in someone who can express it better. I think that we're seeing "mirror" images of goverment energy policies that just use different modalities for accomplishing their goals ..I don't think viscosity is really an issue. That is, Europe may not give a rat's a$$ about the driving populations consumption of gasoline. The taxes on it (probably) fund their public trans system. It's an intergral part of the national "population managment" system. Drivers pay a substantial premium for the right to drive. Self funded and "out of the loop" in terms of degenerative liability We, on the other hand, have such an impact on other sectors of our governments "population management" system with our gasoline consumption ..that this is what they choose to manage.
The problem we all get sucked into is focusing on viscosity alone. This is the wrong way to look at it. Remember, a good 20wt with a strong AW package could out perform a weak 40wt. Stever Bergin of GM was right for the most part all along. Why do you think so many car manuals call for the whole spectrum? 0w-20 to 15-40 etc. ?
On the other hand, if it does die, it'll just be resurrected again under a different title in a week or two. May as well keep all the "wailing and gnashing of teeth" together in one thread.
Ford owns Jaguar. I'm pretty sure the engine engine is the same except the heads and the stuff attached to them.
In the US, the Jag is recommended 10w30 and 5w30 depending on weather. Put the same engine (except the heads) in a Tauras of 500 and it gets recommended 5w20.
I'm not sure of the U.K. recommended viscosity...I suppose I could email a U.K. dealership or the British Jag headquarters.
Let's give it it's own forum, Thick vs. Thin. Worked to consolidate GC discussion.quote:
Originally posted by 427Z06:
On the other hand, if it does die, it'll just be resurrected again under a different title in a week or two. May as well keep all the "wailing and gnashing of teeth" together in one thread.
In the API SM standards, sequence VIB requires 0W-20 and 5W-20 to give 2.3 (when new) and 2.0% (for used oil) better fuel mileage than a "standard oil" of the same viscosity. 1.8 & 1.5% are the requirements for fuel savings for 0W-30 and 5W-30. 1.1 & 0.8% for other viscosity grades. If the oils meet this, they get the "Energy Conserving" labels.
So, 5W-20 gives 2% better mileage, not 2 mpg. I can't see the difference, but nationally it does make a difference.
Haas is also wrong in several points in his write up about oils. He neglects the hydrodynamic lubrication that takes place inside a journal bearing. If the bearing surface area is larger for the mechanical load on it, thinner oil can be safely used. If the bearing surface area is smaller, higher viscosity oil is needed with its higher film strength, subject to the clearances...generally viscosity must be matched to the clearance size. Haas's premise about flow = lubrication is wrong. Flow is only needed for a fresh supply of cooled and filtered oil. If the physical arrangement is possible, a journal bearing runs fine in an oil bath, maybe with a cooler inside the oil reservoir. I've run many for years without problem this way on industrial machinery. A bearing without a rotating journal, such as an oscillating wrist pin, may need the oil pressure to provide lift, again subject to the surface area of the bearing and the load.
Ken
So, 5W-20 gives 2% better mileage, not 2 mpg. I can't see the difference, but nationally it does make a difference.
Haas is also wrong in several points in his write up about oils. He neglects the hydrodynamic lubrication that takes place inside a journal bearing. If the bearing surface area is larger for the mechanical load on it, thinner oil can be safely used. If the bearing surface area is smaller, higher viscosity oil is needed with its higher film strength, subject to the clearances...generally viscosity must be matched to the clearance size. Haas's premise about flow = lubrication is wrong. Flow is only needed for a fresh supply of cooled and filtered oil. If the physical arrangement is possible, a journal bearing runs fine in an oil bath, maybe with a cooler inside the oil reservoir. I've run many for years without problem this way on industrial machinery. A bearing without a rotating journal, such as an oscillating wrist pin, may need the oil pressure to provide lift, again subject to the surface area of the bearing and the load.
Ken
I certainly agree that it's not "better" for the engine. I think it's also not worse. It seems to me that America's junkyard "fleet" is the best evidence on the planet that oil selection and even most drain habits are completely irrelevant to engine life.
IMHO, the simple fact is that 20-weight oils DO exist only for gas mileage; it's just that oil viscosity is one of the least significant factors there is to engine life.
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Does anybody want me to scan my '89 German manual which lists 5W-20 for my VW? I don't know why now some of you claim that 5W-20 oil does not exist in Europe. 5W-20 oil HAVE been around for a long time! Of course that doesn't mean people use them.
If a 5W-30 shears to 5W-20, does that imply a 5W-20 will stay in grade?
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