here is what i think i think 20 weight oils are purely for fuel economy reasons. i think the fed and their cafe standards are more about fuel economy than long term reliability . I think that 5w40 is probably the perfect weight or even 0w40 thin at start up makes good sense. but thin while running to me is stupid. some new cars also don't come with spare tires to save some gas is that a good idea to? i think 20 weights are ok for basic driving but if you ever "drive" your car i would want an oil that was doing more than barely cutting it. when i changed my moms oil and put 5w30 in it instead of 5w20 it sounded and felt much better with 5w20 it always sounds like sewing machine. tick tick tick .... i think thick oil is bad to but a 5w30 or 5w40 is a good weight that almost any car will run forever on.
American love affair for thin oil
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There are quite a few hard worked trucks, taxis, etc that have "run forever" on xw20.
Originally Posted By: tommygunn
If you seriously wanna try to be some elitist [censored] because your country runs thicker oils and you "know" Americans are all a bunch of idiots and its all to blame on the US Government, go ahead.
LOL tommygunn. Not sure if it was intended or not, but I was also reading a bit of that kind of attitude into the OP as well.
If you seriously wanna try to be some elitist [censored] because your country runs thicker oils and you "know" Americans are all a bunch of idiots and its all to blame on the US Government, go ahead.
LOL tommygunn. Not sure if it was intended or not, but I was also reading a bit of that kind of attitude into the OP as well.
For what it's worth, here’s my take on the thick/thin debate.
The oil specified in any given region is probably a compromise between:
- adequate protection under heat + hard driving conditions
- adequate cold start performance
- maintaining good oil flow during regular operation
- cost and availability.
- (and possibly) fuel consumption and emission standards.
The way I see it the main pros and cons in the thick versus thin debate are:
- Film thickness and maximum hydrodynamic pressure are greater with a "thicker" oil.
- However the circulation at cold start will be slower, and even in normal operation the flow rate may be reduced with thicker oil if bypass pressure is reached. Lower flow rate can mean less heat removal from critical parts.
I think that in the past, fear of not maintaining adequate hydrodynamic lubrication under fairly severe operation may have been a factor in not using xW20 oils, other than where it was essential for very low temperature starts. It's probably been the improvement in additive packages that reduce wear under boundary layer lubrication, and also the improved grade stability, that has allowed xW20 use to become more widespread.
In any case, we cant deny the fact that very many cars in the US are running xW20 without any widespread drama. But equally, you cant deny that many in Australia (and elsewhere) are running the same or very similar cars on xW40 and even xW50, again without drama. So I think this tells us that there’s a reasonably wide range of acceptable oil viscosities that most engines can survive on, given a good quality modern motor oil.
It’s probably one of those “what you lose on the swings you gain on the roundabouts” kind of situations. The guys on the thicker oils may be getting slightly better protection under the sustained hard driving conditions and the guys running the thinner oils are getting less cold start wear.
The oil specified in any given region is probably a compromise between:
- adequate protection under heat + hard driving conditions
- adequate cold start performance
- maintaining good oil flow during regular operation
- cost and availability.
- (and possibly) fuel consumption and emission standards.
The way I see it the main pros and cons in the thick versus thin debate are:
- Film thickness and maximum hydrodynamic pressure are greater with a "thicker" oil.
- However the circulation at cold start will be slower, and even in normal operation the flow rate may be reduced with thicker oil if bypass pressure is reached. Lower flow rate can mean less heat removal from critical parts.
I think that in the past, fear of not maintaining adequate hydrodynamic lubrication under fairly severe operation may have been a factor in not using xW20 oils, other than where it was essential for very low temperature starts. It's probably been the improvement in additive packages that reduce wear under boundary layer lubrication, and also the improved grade stability, that has allowed xW20 use to become more widespread.
In any case, we cant deny the fact that very many cars in the US are running xW20 without any widespread drama. But equally, you cant deny that many in Australia (and elsewhere) are running the same or very similar cars on xW40 and even xW50, again without drama. So I think this tells us that there’s a reasonably wide range of acceptable oil viscosities that most engines can survive on, given a good quality modern motor oil.
It’s probably one of those “what you lose on the swings you gain on the roundabouts” kind of situations. The guys on the thicker oils may be getting slightly better protection under the sustained hard driving conditions and the guys running the thinner oils are getting less cold start wear.
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Of course they assume the car will be driven on the Autobahn but a little 1.4 isn't doing a 100MPH all day, its top speed is listed at 168kmh on the flat which is basically only 25 MPH more than the new proposed speed limit in parts of Texas.
By your argument if they need to build in "headroom" for 25 mph are they going to change their recommendation for 5w30 or 0w40 for cars in Texas?
I suspect not all Texans will drive the exact speed limit.
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I'm not saying that it's *not* available, but that selection/supply is limited. Do you disagree?
Limited supply? No. Any Toyota or Honda dealer has it, they have to because hybrids are sold there. Limited retail store availability? Yes okay.
The 5w20 spec for hybrids is for mostly around town they spec higher for mostly all gas useage.
XOM has a huge presence there, if they wanted 5w20 they could have it by the boat load in no time at all.
So with fuel costing 8-10 bucks a gallon and if this oil offered the same protection why don't they spec it?
Believe me the average German can comprehend the argument and is more than willing to accept lighter oils if in fact they offer the same or better protection.
They had no problem moving to 5w30 from 15w40 in the mid 80's when it was proven capable.
At his point 20w oils have not been proven to their satisfaction (by their i mean the various testing agency's), thats not to say that in the future it will not see widespread use just not now.
I was reading that every Chrysler SRT car will now be spec for 0w40 in the US. Obviously Chrysler doent think 5w20 is capable of protecting the engines used in these cars and driven the US.
Maybe they need to read BITOG and the experts here to get the right idea.
All they need is high VII and the right HTHS and they will be good to go.
By your argument if they need to build in "headroom" for 25 mph are they going to change their recommendation for 5w30 or 0w40 for cars in Texas?
I suspect not all Texans will drive the exact speed limit.
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I'm not saying that it's *not* available, but that selection/supply is limited. Do you disagree?
Limited supply? No. Any Toyota or Honda dealer has it, they have to because hybrids are sold there. Limited retail store availability? Yes okay.
The 5w20 spec for hybrids is for mostly around town they spec higher for mostly all gas useage.
XOM has a huge presence there, if they wanted 5w20 they could have it by the boat load in no time at all.
So with fuel costing 8-10 bucks a gallon and if this oil offered the same protection why don't they spec it?
Believe me the average German can comprehend the argument and is more than willing to accept lighter oils if in fact they offer the same or better protection.
They had no problem moving to 5w30 from 15w40 in the mid 80's when it was proven capable.
At his point 20w oils have not been proven to their satisfaction (by their i mean the various testing agency's), thats not to say that in the future it will not see widespread use just not now.
I was reading that every Chrysler SRT car will now be spec for 0w40 in the US. Obviously Chrysler doent think 5w20 is capable of protecting the engines used in these cars and driven the US.
Maybe they need to read BITOG and the experts here to get the right idea.
All they need is high VII and the right HTHS and they will be good to go.
Originally Posted By: Brigadier
So, it is unsound logic to deduce that the laws of physics apply to 20W oils just like they do with 30W, 40W oils? Logic dictates that if a 30W or 40W oil shears to a lower viscostiy range, then the same MUST be said for a 20W oil, or have you fanboys overcome the laws of physics in your newfangled 20W oils?
since you've just devolved into personal attacks, I'm not going to bother responding. The evidence to answer your question is readily available. Look it up for yourself.
So, it is unsound logic to deduce that the laws of physics apply to 20W oils just like they do with 30W, 40W oils? Logic dictates that if a 30W or 40W oil shears to a lower viscostiy range, then the same MUST be said for a 20W oil, or have you fanboys overcome the laws of physics in your newfangled 20W oils?
since you've just devolved into personal attacks, I'm not going to bother responding. The evidence to answer your question is readily available. Look it up for yourself.
Originally Posted By: Trav
At his point 20w oils have not been proven to their satisfaction (by their i mean the various testing agency's), thats not to say that in the future it will not see widespread use just not now.
I wonder how much of this is due to the fact that most of the oils and testing are for dual rated oils? All of the ACEA engine tests of which I'm aware also have a diesel component, which have difference requirements than gasoline engines (much higher fuel dilution, much higher soot levels). I wonder if this plays a part in oil availability (I don't know, I'm just asking the question).
Originally Posted By: Trav
Maybe they need to read BITOG and the experts here to get the right idea.
All they need is high VII and the right HTHS and they will be good to go.
Funny, I thought the "thin oil crowd" were the ones engaged in straw man arguments... Maybe the engine operates under a regime where it needs a heavier-viscosity oil?
At his point 20w oils have not been proven to their satisfaction (by their i mean the various testing agency's), thats not to say that in the future it will not see widespread use just not now.
I wonder how much of this is due to the fact that most of the oils and testing are for dual rated oils? All of the ACEA engine tests of which I'm aware also have a diesel component, which have difference requirements than gasoline engines (much higher fuel dilution, much higher soot levels). I wonder if this plays a part in oil availability (I don't know, I'm just asking the question).
Originally Posted By: Trav
Maybe they need to read BITOG and the experts here to get the right idea.
All they need is high VII and the right HTHS and they will be good to go.
Funny, I thought the "thin oil crowd" were the ones engaged in straw man arguments... Maybe the engine operates under a regime where it needs a heavier-viscosity oil?
I agree JOD we can have differences of opinion and argue, debate or whatever else but there is no need for personal attacks.
I respect your opinion even if i don't agree with it, you do think the argument through any way and thats what a Forum is all about.
Okay back at it
I respect your opinion even if i don't agree with it, you do think the argument through any way and thats what a Forum is all about.
Okay back at it
Well the diesel point is valid. I don't have an answer.
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Maybe the engine operates under a regime where it needs a heavier-viscosity oil?
Yeah maybe
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Maybe the engine operates under a regime where it needs a heavier-viscosity oil?
Yeah maybe
Thin skins abound, and I guess tongue in cheek sarcasm is not allowed? Come on guys, relax. Sheesh.
Originally Posted By: JOD
Originally Posted By: Brigadier
So, it is unsound logic to deduce that the laws of physics apply to 20W oils just like they do with 30W, 40W oils? Logic dictates that if a 30W or 40W oil shears to a lower viscostiy range, then the same MUST be said for a 20W oil, or have you fanboys overcome the laws of physics in your newfangled 20W oils?
since you've just devolved into personal attacks, I'm not going to bother responding. The evidence to answer your question is readily available. Look it up for yourself.
Originally Posted By: JOD
Originally Posted By: Brigadier
So, it is unsound logic to deduce that the laws of physics apply to 20W oils just like they do with 30W, 40W oils? Logic dictates that if a 30W or 40W oil shears to a lower viscostiy range, then the same MUST be said for a 20W oil, or have you fanboys overcome the laws of physics in your newfangled 20W oils?
since you've just devolved into personal attacks, I'm not going to bother responding. The evidence to answer your question is readily available. Look it up for yourself.
Originally Posted By: Brigadier
Originally Posted By: JOD
Originally Posted By: Brigadier
It.......was..........just..........a.........question!!! Boy, you thin oil fanboys sure do get defensive at the drop of a hat........
So, on one hand I am supposed to take UOA as gospel, but then everyone here says Blackstone's UOA's are suspect. Hmmmmmmm.......
So, criticize me, but don't actually answer the question. Got it. I'm not a "thin oil fanboy", I just hate unsound logic. Personally, I think there will be marginal differences and that frankly viscosity doesn't make that big a difference WRT engine wear. Do I think a thinner oil will protect a little better in my situation? Yeah, I do; but I also realize the difference is minimal. I just grow weary of all of the unfounded nonsense that gets tossed around.
And, who ever said UOA's were suspect for determining oil viscosity? Determining wear? Sure. Viscosity just isn't that difficult to test reliably or repeatedly. Again, you're making stuff up to suit your own agenda.
So, it is unsound logic to deduce that the laws of physics apply to 20W oils just like they do with 30W, 40W oils? Logic dictates that if a 30W or 40W oil shears to a lower viscostiy range, then the same MUST be said for a 20W oil, or have you fanboys overcome the laws of physics in your newfangled 20W oils?
5W20 tends to be more sheer stable than 5W30 0W30 and especially 5W40 and 0W40.
Originally Posted By: JOD
Originally Posted By: Brigadier
It.......was..........just..........a.........question!!! Boy, you thin oil fanboys sure do get defensive at the drop of a hat........
So, on one hand I am supposed to take UOA as gospel, but then everyone here says Blackstone's UOA's are suspect. Hmmmmmmm.......
So, criticize me, but don't actually answer the question. Got it. I'm not a "thin oil fanboy", I just hate unsound logic. Personally, I think there will be marginal differences and that frankly viscosity doesn't make that big a difference WRT engine wear. Do I think a thinner oil will protect a little better in my situation? Yeah, I do; but I also realize the difference is minimal. I just grow weary of all of the unfounded nonsense that gets tossed around.
And, who ever said UOA's were suspect for determining oil viscosity? Determining wear? Sure. Viscosity just isn't that difficult to test reliably or repeatedly. Again, you're making stuff up to suit your own agenda.
So, it is unsound logic to deduce that the laws of physics apply to 20W oils just like they do with 30W, 40W oils? Logic dictates that if a 30W or 40W oil shears to a lower viscostiy range, then the same MUST be said for a 20W oil, or have you fanboys overcome the laws of physics in your newfangled 20W oils?
5W20 tends to be more sheer stable than 5W30 0W30 and especially 5W40 and 0W40.
LOL accent, no wonder I keep losing oil if it's too thin. I forgot about being upside down!
Seriously though, there's one other factor that I think is holding lots of Aussies back from using thinner oils, and that's price. Not sure why, probably market volumes I guess, but good quality 5W30 oils here are often nearly twice the price compared with some very decent 10W40 and 15W40 alternatives.
Seriously though, there's one other factor that I think is holding lots of Aussies back from using thinner oils, and that's price. Not sure why, probably market volumes I guess, but good quality 5W30 oils here are often nearly twice the price compared with some very decent 10W40 and 15W40 alternatives.
Originally Posted By: uart
Seriously though, there's one other factor that I think is holding lots of Aussies back from using thinner oils, and that's price. Not sure why, probably market volumes I guess, but good quality 5W30 oils here are often nearly twice the price compared with some very decent 10W40 and 15W40 alternatives.
Well no wonder 5W30 or 5W20 isn't recommended there.
Seriously though, there's one other factor that I think is holding lots of Aussies back from using thinner oils, and that's price. Not sure why, probably market volumes I guess, but good quality 5W30 oils here are often nearly twice the price compared with some very decent 10W40 and 15W40 alternatives.
Well no wonder 5W30 or 5W20 isn't recommended there.
Originally Posted By: Brigadier
Originally Posted By: JOD
Originally Posted By: Brigadier
It.......was..........just..........a.........question!!! Boy, you thin oil fanboys sure do get defensive at the drop of a hat........
So, on one hand I am supposed to take UOA as gospel, but then everyone here says Blackstone's UOA's are suspect. Hmmmmmmm.......
So, criticize me, but don't actually answer the question. Got it. I'm not a "thin oil fanboy", I just hate unsound logic. Personally, I think there will be marginal differences and that frankly viscosity doesn't make that big a difference WRT engine wear. Do I think a thinner oil will protect a little better in my situation? Yeah, I do; but I also realize the difference is minimal. I just grow weary of all of the unfounded nonsense that gets tossed around.
And, who ever said UOA's were suspect for determining oil viscosity? Determining wear? Sure. Viscosity just isn't that difficult to test reliably or repeatedly. Again, you're making stuff up to suit your own agenda.
So, it is unsound logic to deduce that the laws of physics apply to 20W oils just like they do with 30W, 40W oils? Logic dictates that if a 30W or 40W oil shears to a lower viscostiy range, then the same MUST be said for a 20W oil, or have you fanboys overcome the laws of physics in your newfangled 20W oils?
Do not take this as a personal attack. But you have stated you have a engineering background. You can look at the characteristics of what causes shearing. I will give you a hint 5W-50 oils have a tendency to shear into 30 grade oils. Why do you suppose that is?
Originally Posted By: JOD
Originally Posted By: Brigadier
It.......was..........just..........a.........question!!! Boy, you thin oil fanboys sure do get defensive at the drop of a hat........
So, on one hand I am supposed to take UOA as gospel, but then everyone here says Blackstone's UOA's are suspect. Hmmmmmmm.......
So, criticize me, but don't actually answer the question. Got it. I'm not a "thin oil fanboy", I just hate unsound logic. Personally, I think there will be marginal differences and that frankly viscosity doesn't make that big a difference WRT engine wear. Do I think a thinner oil will protect a little better in my situation? Yeah, I do; but I also realize the difference is minimal. I just grow weary of all of the unfounded nonsense that gets tossed around.
And, who ever said UOA's were suspect for determining oil viscosity? Determining wear? Sure. Viscosity just isn't that difficult to test reliably or repeatedly. Again, you're making stuff up to suit your own agenda.
So, it is unsound logic to deduce that the laws of physics apply to 20W oils just like they do with 30W, 40W oils? Logic dictates that if a 30W or 40W oil shears to a lower viscostiy range, then the same MUST be said for a 20W oil, or have you fanboys overcome the laws of physics in your newfangled 20W oils?
Do not take this as a personal attack. But you have stated you have a engineering background. You can look at the characteristics of what causes shearing. I will give you a hint 5W-50 oils have a tendency to shear into 30 grade oils. Why do you suppose that is?
Originally Posted By: Shannow
Sorry mate, you aren't in Fords field of expert engineers, nor have you contributed the dollars in engineering and verification...
I've not seen Ford, nor their engineers even suggest a bell curve, but more a vertical line.
And they are right, you know, as they have spent millions and decades on it !!!
Huh?
Sorry mate, you aren't in Fords field of expert engineers, nor have you contributed the dollars in engineering and verification...
I've not seen Ford, nor their engineers even suggest a bell curve, but more a vertical line.
And they are right, you know, as they have spent millions and decades on it !!!
Huh?
Originally Posted By: Shannow
Originally Posted By: Jim Allen
Circular defense of thin oils?
Shannow you claim to have an engineering background. Do you also have the resources to run the same sorts of qualification tests a big company like Ford uses to certify oil? Until you do, I submit that, if you are intellectually honest, you have to give those tests a great deal of credence.
See, you have just stated that "Ford said", and anyone who hasn't the engineering resources of Ford, nor applied same to THAT question can comment with credibility.
Which in turn makes your own argument "Ford said", as you haven't the capability to independently verify.
Last time I checked, the laws of physics weren't brand specific, nor did they waver depending on how much $$$ is thrown at it.
For a given load, critical dimensions and speed, a 20 will have a lower film thickness than a 30...is it important ?
Maybe
It's important enough for Ford to be adapting their bearings to 20 weight in the ecoboost with their much higher power densities than that which they have manufactured for (probably the same decades that they've been offering xW-30)
You are reinforcing my argument here. They are evolving the viscosity requirements according to the engine and and the operating conditions. That's what they SHOULD be doing. Shows they are on the ball. That's the concept I've been trying to impress on the "thick oil fanboys."
Every engine has a "three bears" point; too thick, too thin and just right. I contend that, for the most part, the OE knows that "just right" point better than a bunch of internet theorists (of which I am but one) so I give their recommendations a lot of weight. In other words, given my limited expertise and resources, who do I trust more? A battalion of engineers at a company that has spent millions to qualify an oil viscosity for my engine, or a bunch of "so-called self-appointed oil gurus" (to quote Brigadier's description of me)? The answer seems clear to me, but obviously not to others.
Of course 20 grade has less film thickness that 30 grade. I'm not arguing that point. All I want you to grasp is that Ford went through an elaborate certification process to verify that most of their engines of were adequately protected on 20 grade. The ones that weren't, or the situations where the ones that were might not be adequately protected, are documented in the manuals. No doubt they made mistakes in some areas but the 10 years since they switched over has more or less proven them right. Whatever their motivation for adopting 5W20 oils, it's worked out just fine. Is it optimal in every case. NO! I've typed it so many times here that my already gnarled fingers are now resembling bony claws. Is it adequate in the cases where it's spec'ed, in the overwhelmingly high percentage, yes.
Can we agree on that much, at least?
I never knew how few motor vehicles there were in Australia until I checked, 16.4 million as of last year. It's entirely possible that there are more Ford vehicles on the road in the USA running on 5W20 than there are cars on the road period in Australia. In light of this incredible thread, that makes me smile. Seems certain that there are more vehicles of all types in the USA running 5W20 than there are vehicles in Australia. Interestingly, the per-capita vehicle ownership isn't all that far apart, 808/1000 in the USA vs 730/1000 in AUS.
Originally Posted By: Jim Allen
Circular defense of thin oils?
Shannow you claim to have an engineering background. Do you also have the resources to run the same sorts of qualification tests a big company like Ford uses to certify oil? Until you do, I submit that, if you are intellectually honest, you have to give those tests a great deal of credence.
See, you have just stated that "Ford said", and anyone who hasn't the engineering resources of Ford, nor applied same to THAT question can comment with credibility.
Which in turn makes your own argument "Ford said", as you haven't the capability to independently verify.
Last time I checked, the laws of physics weren't brand specific, nor did they waver depending on how much $$$ is thrown at it.
For a given load, critical dimensions and speed, a 20 will have a lower film thickness than a 30...is it important ?
Maybe
It's important enough for Ford to be adapting their bearings to 20 weight in the ecoboost with their much higher power densities than that which they have manufactured for (probably the same decades that they've been offering xW-30)
You are reinforcing my argument here. They are evolving the viscosity requirements according to the engine and and the operating conditions. That's what they SHOULD be doing. Shows they are on the ball. That's the concept I've been trying to impress on the "thick oil fanboys."
Of course 20 grade has less film thickness that 30 grade. I'm not arguing that point. All I want you to grasp is that Ford went through an elaborate certification process to verify that most of their engines of were adequately protected on 20 grade. The ones that weren't, or the situations where the ones that were might not be adequately protected, are documented in the manuals. No doubt they made mistakes in some areas but the 10 years since they switched over has more or less proven them right. Whatever their motivation for adopting 5W20 oils, it's worked out just fine. Is it optimal in every case. NO! I've typed it so many times here that my already gnarled fingers are now resembling bony claws. Is it adequate in the cases where it's spec'ed, in the overwhelmingly high percentage, yes.
Can we agree on that much, at least?
I never knew how few motor vehicles there were in Australia until I checked, 16.4 million as of last year. It's entirely possible that there are more Ford vehicles on the road in the USA running on 5W20 than there are cars on the road period in Australia. In light of this incredible thread, that makes me smile. Seems certain that there are more vehicles of all types in the USA running 5W20 than there are vehicles in Australia. Interestingly, the per-capita vehicle ownership isn't all that far apart, 808/1000 in the USA vs 730/1000 in AUS.
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