It has been stated several times on BITOG, that a car/truck manufactures engineers know what is the best weight engine oil for a particular engine and that is why they spec that weight in the owners manual. Is this always true? Do the manufactures and engineers really design an engine around one or at most two particular weights of engine oil?
Automotive engineers and oil
- Thread starter Moondawg
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MolaKule
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IN terms of engine engineers, I would say that according to the laws and constraints (EPA and lawyers) they work under, yes.
I really have my doubts about manual transmission and differential engineers. They seem to know their ME theory but often lack in lubrication knowledge.
I really have my doubts about manual transmission and differential engineers. They seem to know their ME theory but often lack in lubrication knowledge.
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Every engineer who joins an OEM wants to design a Ferrari.
However not everyone can design a Ferrari, so some engineers settle for designing other cars.
Not anyone can design a car, so some engineers design engines. Others settle for designing interiors. Other have to settle for designing door handles and exhaust pipes.
The guy that looks after oils in an OEM never had a hope in [censored] of doing any of the above jobs. He can't imagine, he can't draw, he doesn't know one end of a spanner from the other. In fact he was the person that settled for the position of Safety Officer but flunked the job interview.
You think I'm joking? Nope...not a bit of it.
However not everyone can design a Ferrari, so some engineers settle for designing other cars.
Not anyone can design a car, so some engineers design engines. Others settle for designing interiors. Other have to settle for designing door handles and exhaust pipes.
The guy that looks after oils in an OEM never had a hope in [censored] of doing any of the above jobs. He can't imagine, he can't draw, he doesn't know one end of a spanner from the other. In fact he was the person that settled for the position of Safety Officer but flunked the job interview.
You think I'm joking? Nope...not a bit of it.
They design the ENGINE to do its job. Then they pick an oil that provides the best all-around combination of protection and efficiency. Sometimes they screw up the engine design (BMW, I'm looking at you...) and have to spec 60-weight oil to make engine bearings live, but its relatively rare. I think its an overstatement when people say "5w20 is all about fuel economy" when so many engines have been observed go 200,000 and more miles on it. But fuel economy certainly is a factor when the manufacturer comes up with a spec., but I think first and foremost they look at meeting a minimum level of engine protection. And dont forget sometimes thin is better: higher flow through timing chain sprayers and under-piston sprayers may be something that the manufacturer specifically WANTS for better protection, not just economy.
In the case of things like variable valve timing, older diesel HEUI systems, and cylinder deactivation that depend on the oil as a hydraulic fluid to actuate mechanical components, the timing of those actuations as measured by the engine controller may also depend on the fluid (oil) being in the right thickness regime. Granted, there's a lot of tolerance built into most of those systems, but there have been cases of people throwing Xw30 or Xw40 oil in their MDS/VCT Hemi because "5w20 is all about fuel economy and I don't care about that" and then getting error codes with one of the system's response time is outside the tolerance allowed by the controller. No *damage*, but an error code that goes away when thinner oil is put back in.
In the case of things like variable valve timing, older diesel HEUI systems, and cylinder deactivation that depend on the oil as a hydraulic fluid to actuate mechanical components, the timing of those actuations as measured by the engine controller may also depend on the fluid (oil) being in the right thickness regime. Granted, there's a lot of tolerance built into most of those systems, but there have been cases of people throwing Xw30 or Xw40 oil in their MDS/VCT Hemi because "5w20 is all about fuel economy and I don't care about that" and then getting error codes with one of the system's response time is outside the tolerance allowed by the controller. No *damage*, but an error code that goes away when thinner oil is put back in.
That question is like asking, which religion is the best. The Bible can be interpreted to suit anyone's beliefs. It's a guideline for life, like an car makers recommendation is a guideline for oil use. Use what you want, and believe what you want. Sometimes what they say doesn't make sense. Like Harley for instance, they only recommend their brand of oil, or diesel oil. Which one is the best to use?.,,,
If engineers were allowed to design and build exactly what they thought was a great car it would certainly be a lot different from the one that gets produced. And if produced this wonderful car would probably be the end of the manufacturer.
440Magnum you are absolutely correct. And when the engineers do mess up then the dealers get a TSB about it.
Originally Posted By: Moondawg
It has been stated several times on BITOG, that a car/truck manufactures engineers know what is the best weight engine oil for a particular engine and that is why they spec that weight in the owners manual. Is this always true?
if it's true why the toyota's 2GR-FE engine is specified for 5W30 or 5W20 oils (depending on year or car) in US, while outside US, 10W30 is the thinnest oil, allowed only during cold winters and 5W40 and up cover summer temps?
It has been stated several times on BITOG, that a car/truck manufactures engineers know what is the best weight engine oil for a particular engine and that is why they spec that weight in the owners manual. Is this always true?
if it's true why the toyota's 2GR-FE engine is specified for 5W30 or 5W20 oils (depending on year or car) in US, while outside US, 10W30 is the thinnest oil, allowed only during cold winters and 5W40 and up cover summer temps?
Originally Posted By: Joe90_guy
Every engineer who joins an OEM wants to design a Ferrari.
However not everyone can design a Ferrari, so some engineers settle for designing other cars.
Not anyone can design a car, so some engineers design engines. Others settle for designing interiors. Other have to settle for designing door handles and exhaust pipes.
The guy that looks after oils in an OEM never had a hope in [censored] of doing any of the above jobs. He can't imagine, he can't draw, he doesn't know one end of a spanner from the other. In fact he was the person that settled for the position of Safety Officer but flunked the job interview.
You think I'm joking? Nope...not a bit of it.
How do you "flunk" a job interview?
Every engineer who joins an OEM wants to design a Ferrari.
However not everyone can design a Ferrari, so some engineers settle for designing other cars.
Not anyone can design a car, so some engineers design engines. Others settle for designing interiors. Other have to settle for designing door handles and exhaust pipes.
The guy that looks after oils in an OEM never had a hope in [censored] of doing any of the above jobs. He can't imagine, he can't draw, he doesn't know one end of a spanner from the other. In fact he was the person that settled for the position of Safety Officer but flunked the job interview.
You think I'm joking? Nope...not a bit of it.
How do you "flunk" a job interview?
Originally Posted By: HerrStig
]How do you "flunk" a job interview?
I'd say if you flunked the interview you won't get the job.
]How do you "flunk" a job interview?
I'd say if you flunked the interview you won't get the job.
If there was no CAFE, would we see any 20 wt oil on the market?
Originally Posted By: demarpaint
Originally Posted By: HerrStig
]How do you "flunk" a job interview?
I'd say if you flunked the interview you won't get the job.
In this case apparently when you flunk the job interview they hire you as Chief Lubrication Engineer. At which point you get the unenviable job of rolling a die to decide which SAE grade to print in the manual.
Originally Posted By: HerrStig
]How do you "flunk" a job interview?
I'd say if you flunked the interview you won't get the job.
In this case apparently when you flunk the job interview they hire you as Chief Lubrication Engineer. At which point you get the unenviable job of rolling a die to decide which SAE grade to print in the manual.
Maybe 'flunk' is like 'spunk' and has a different meaning either side of The Pond...
Originally Posted By: Inspecktor
If there was no CAFE, would we see any 20 wt oil on the market?
Even without CAFE, fuel economy matters in the world we live in.
If there was no CAFE, would we see any 20 wt oil on the market?
Even without CAFE, fuel economy matters in the world we live in.
I'd say yes they do, within the constraints they are dealing with - CAFE/EPA etc.
What people fail to realize is that while many of these regulations create problems and headaches for engineers, it can and often does lead to better improved technology.
Simply put, today's engines/oils are lasting longer than any other point in history. So despite all the crying about CAFE and low viscosity, engines are living LONGER NOT SHORTER.
What people fail to realize is that while many of these regulations create problems and headaches for engineers, it can and often does lead to better improved technology.
Simply put, today's engines/oils are lasting longer than any other point in history. So despite all the crying about CAFE and low viscosity, engines are living LONGER NOT SHORTER.
Originally Posted By: Inspecktor
If there was no CAFE, would we see any 20 wt oil on the market?
Good question, but necessity is the mother of invention. I think we all benefit from the CAFE requirements - engineers work better with challenges - excepting some VW examples.
If there was no CAFE, would we see any 20 wt oil on the market?
Good question, but necessity is the mother of invention. I think we all benefit from the CAFE requirements - engineers work better with challenges - excepting some VW examples.
Originally Posted By: NateDN10
Originally Posted By: demarpaint
Originally Posted By: HerrStig
]How do you "flunk" a job interview?
I'd say if you flunked the interview you won't get the job.
In this case apparently when you flunk the job interview they hire you as Chief Lubrication Engineer. At which point you get the unenviable job of rolling a die to decide which SAE grade to print in the manual.
That's quite possible, hopefully not the case though.
Originally Posted By: demarpaint
Originally Posted By: HerrStig
]How do you "flunk" a job interview?
I'd say if you flunked the interview you won't get the job.
In this case apparently when you flunk the job interview they hire you as Chief Lubrication Engineer. At which point you get the unenviable job of rolling a die to decide which SAE grade to print in the manual.
That's quite possible, hopefully not the case though.
I suspect it happens less now but in days gone by, there were several instances of oil companies running multi-million dollar oil development programs at the behest of OEMs, only to find the OEM oil guys wouldn't/couldn't 'officialise' use of the new oil by amending the manual.
Nick1994
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I believe they do design an engine around 0w20, that's what almost all the cars are getting now except for German cars.
So if they designed an engine, and THEN decided what oil suits it best, it sure is interesting that all the cars now call for 0w20. Sounds to me like they say that's the oil that will be used regardless, and the engine that is built needs to be able to handle it.
So if they designed an engine, and THEN decided what oil suits it best, it sure is interesting that all the cars now call for 0w20. Sounds to me like they say that's the oil that will be used regardless, and the engine that is built needs to be able to handle it.
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