Are we seeing more oil related failures in modern cars?

Kestas

Staff member
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I don’t think it’s the oil really, I think it’s people either forgetting or not caring about changing the oil and letting it run low.
I too think this is the best answer. Let me point out that in the old days the owners manual would show how to adjust the valves. Now manuals tell you not to drink the washer fluid. Car owners have gotten dumber.
 
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While I believe half the problems people have are caused by them, lousy engineering makes up the other half, and trying to milk the last mile out of an oil change makes up the smallest part. People being impatient. starting an ice cold motor and flooring it before the motor has spun 1,000 rpms, might just hasten the failure process. I've also noticed alot of cars for sale with transmission failures. Seems they always take the car to the car wash, but never even think about having the transmission fluid changed. And if you ask someone about changing it, they'll look at you funny and say something like, I don't think it needs to be done on my car. Kinda like when you ask someone ,when was the last time you changed the oil in your lawnmower. Again driving your car like your in a Nascar race, all the time will cause expensive parts to quit before there time. You can use the best brand of oil know to man, but if you let it run low, or never change it, it will do it's job until it's given your motor all it can. And no one will take the blame for ruining the motor, so it must be the oil.,,,
Most new cars can go 75k or more on factory fill trans oil...Most trans failures I know of are the new CVT .....nissan being the worse.....almost to the point its going to fail before 100k .....most at 75k.
If Most would read the owners maintenance guide most problems would be cut in half.....and of course follow it.
 
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While I believe half the problems people have are caused by them, lousy engineering makes up the other half, and trying to milk the last mile out of an oil change makes up the smallest part. People being impatient. starting an ice cold motor and flooring it before the motor has spun 1,000 rpms, might just hasten the failure process. I've also noticed alot of cars for sale with transmission failures. Seems they always take the car to the car wash, but never even think about having the transmission fluid changed. And if you ask someone about changing it, they'll look at you funny and say something like, I don't think it needs to be done on my car. Kinda like when you ask someone ,when was the last time you changed the oil in your lawnmower. Again driving your car like your in a Nascar race, all the time will cause expensive parts to quit before there time. You can use the best brand of oil know to man, but if you let it run low, or never change it, it will do it's job until it's given your motor all it can. And no one will take the blame for ruining the motor, so it must be the oil.,,,
I agree on the hard driving with cold engines/transmissions part.

However most modern engines have turbos which heat up the oil fast and or water/oil heat exchangers.

With these technologys the oils warms up about 3 times as fast as oldschool engines.
Also the turbos are sometjmes also coolant cooled which also helps heat up the coolant much faster.
Some engines also use a headifold which is the manifold intergrated in the head so it heats up faster.

This in combination with the 0w20 0w30 oil and much beter tolerancrs for head gaskets and pistons/oil clearances really reduces the wear potential.

Oldschool engines needed an almost 20+ minute drive to get out of the "danger" zone for an engine. Especially in cities even longer.
I think modern engines are out of that "zone" in about 5 a 8 minutes.
Then the water is about 60 celcius and the oil also around 60 celcius due to the heat exchanger.

This is in moderate climates.

I personally never give cold cars more than 30 40 percent of their maximum load and as short as possible.
 
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It may be a combination of two things. One, the younger generation are key turners and nothing more. Cars are so good now it's easy to get complacent and not do minor maintenance like "add oil". Secondly, automotive engineers ARE pushing the limits more. With finite element analysis, they are able to design parts so the stress is closer to the edge, on ALL parts. Think of it this way, back in the 70-80's, it was un-heard of for a wheel bearing to go bad. So in effect, wheel bearings were over-designed. Then CAFE hit and every part was optomized....meaning it was designed to be as light as possible. Now quite often, wheel bearings are almost a wear item.....many are now replaced. I think they are now designing engines so close to failure that yeah, your going to see more. But on the other side of it, they are also doing much better testing to prevent these failures. Our engineering has improved.....but you still got to put oil in the **** thing.....
 
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I think auto manufactures are trying to push the envelope as far as they can going thinner and thinner with motor oil. I'v never heard of "oil consumption being normal" until recently. I've never once owned a car that used oil. Thinnest I've ever gone was 10W30. As far back as I can remember,5W30 came into play as a "fuel economy oil". My 300ZX fsm warned in bold type to only use 5W30 if operating temps were below freezing (Fahrenheit). Then it went on to say in bold type to never use a W20 oil.
 
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I think auto manufactures are trying to push the envelope as far as they can going thinner and thinner with motor oil. I'v never heard of "oil consumption being normal" until recently. I've never once owned a car that used oil. Thinnest I've ever gone was 10W30. As far back as I can remember,5W30 came into play as a "fuel economy oil". My 300ZX fsm warned in bold type to only use 5W30 if operating temps were below freezing (Fahrenheit). Then it went on to say in bold type to never use a W20 oil.
I partly agree on this, yes they are going thinner and thinner for fuel consumption. But also the tooling and machining in large scale production has improved so much that the tolerances are so fine that the oil doest not have to fill those large''caves'' any more.

Ive heard stories that the current formule 1 and motogp factory engines run on w8 single grade oil, the engines are always started hot and the tolerances are EXTREMELY tight/perfect, and no they are not allowed to use an unlimted amount of engines any more. Engines failures/changes results in grid and money penalties.
 
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Indiana
It may be a combination of two things. One, the younger generation are key turners and nothing more. Cars are so good now it's easy to get complacent and not do minor maintenance like "add oil". Secondly, automotive engineers ARE pushing the limits more. With finite element analysis, they are able to design parts so the stress is closer to the edge, on ALL parts. Think of it this way, back in the 70-80's, it was un-heard of for a wheel bearing to go bad. So in effect, wheel bearings were over-designed. Then CAFE hit and every part was optomized....meaning it was designed to be as light as possible. Now quite often, wheel bearings are almost a wear item.....many are now replaced. I think they are now designing engines so close to failure that yeah, your going to see more. But on the other side of it, they are also doing much better testing to prevent these failures. Our engineering has improved.....but you still got to put oil in the **** thing.....
Slightly OT but those (very common) wheel bearing problems are almost all due to 3rd world (aka China) quality from suppliers. Having designed spindles and bearings for off road haul trucks back in my early years, the bearing size is dictated by the spindle diameter which is sized for bending fatigue strength. So I think the bearings are big enough but the metallurgy is lousy.
 
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Houston, TX
Historically speaking, oil is of higher quality covering more attributes than it ever has. Owner negligence or design issues likely cause more failures than anything related to oil.
 
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2,017
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Minnesota
Slightly OT but those (very common) wheel bearing problems are almost all due to 3rd world (aka China) quality from suppliers. Having designed spindles and bearings for off road haul trucks back in my early years, the bearing size is dictated by the spindle diameter which is sized for bending fatigue strength. So I think the bearings are big enough but the metallurgy is lousy.
I might agree with you but don't you think with today's FEA that we are running with less factor of safety than we did in the past? Seems when engineers do hand calculations, they like to fudge in the direction of safety, up-sizing compoonents. FEA allows us to design closer to the edge.

As far as 3rd world quality (China).....let me just say, in the very near future youre going to realize they are leapfrogging us and will have superior engineering in mechanical (probaby already do) and electrical. Software they are behind a bit but rapidly catching up. Besides, it's up to the purchaser (car companies) to be quality testing what the low cost producer is offering, if you decide to go with the bottom end product.
 
Part of it as mentioned before is that people just don't check their oil. Years ago it was not uncommon to see people checking it at the pump. Now when I pop the hood to check my oil when fueling people look at me like I am a wierdo.

I check my oil regularly while at a gas pump. I do it out of "old school" habit, not because my car leaks or burns/consumes oil, but because it feels normal to me and reassures me that I can stomp on it without abusing it; and yes, people look at me funny. However, my self-esteem is not subject to public opinion.
 
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