5W-40 All year round?
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wemay
Site Donor 2023
Shannow, interesting link. So I looked up my vehicle and it too recommends 5w40 along with other viscosities. Nowhere in my OM does it do so, but in this link, there it is. Odd.
My concern is protection over performance anyway so I may be joining the OP if the consensus is 40 'protects' better. Who knows.
My concern is protection over performance anyway so I may be joining the OP if the consensus is 40 'protects' better. Who knows.
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I know one thing for sure: there was one summer when I added one quart VSP 5W-40 to 4 quarts of VML 10W-30 on a 100 degree day. That VSP was so thin, it went down the funnel before I could even blink. I can't see it putting any strain on the oil pump at 100 degrees F anyway; that's for sure. Maybe at -40 F it might.
Originally Posted By: Shannow
So....the "engineers" got it right when they specify a light oil, meaning that you should never second guess them and go heavier, as they covered all the bases in their recommendation.
But they got it wrong, in that you can always (in general) go lighter than their recommendation...
So are the engineers right, or wrong ?
Or are they only wrong when they specify 30 or higher ?
Nice attempt to obfuscate the issue.
No the auto engineers aren't wrong, they can't afford to be. That's why in a modern late model car you can safely use the lightest oil grade recommended without concern; there is no lubrication benefit to using anything heavier.
On the off chance that oil temp's do get too high the electronic safeties will kick in to prevent any engine damage.
Fortunately here in NA it's the lightest oil grade recommended that's what is universally used by dealers.
So....the "engineers" got it right when they specify a light oil, meaning that you should never second guess them and go heavier, as they covered all the bases in their recommendation.
But they got it wrong, in that you can always (in general) go lighter than their recommendation...
So are the engineers right, or wrong ?
Or are they only wrong when they specify 30 or higher ?
Nice attempt to obfuscate the issue.
No the auto engineers aren't wrong, they can't afford to be. That's why in a modern late model car you can safely use the lightest oil grade recommended without concern; there is no lubrication benefit to using anything heavier.
On the off chance that oil temp's do get too high the electronic safeties will kick in to prevent any engine damage.
Fortunately here in NA it's the lightest oil grade recommended that's what is universally used by dealers.
wemay
Site Donor 2023
Originally Posted By: CATERHAM
Fortunately here in NA it's the lightest oil grade recommended that's what is universally used by dealers.
CATERHAM, i dont think Shannow was trying to obfuscate the issue.
This is certainly true, Hyundai does use 5w30 conventional at the dealerships with the 'free' oil changes and if you chose to pay more, synthetic in 5w30 as well since this appears to be the bulk grade. But why would they also offer a recommendation for the 40 grade and qualify it with the 'for improved vehicle performance' phrase?
Fortunately here in NA it's the lightest oil grade recommended that's what is universally used by dealers.
CATERHAM, i dont think Shannow was trying to obfuscate the issue.
This is certainly true, Hyundai does use 5w30 conventional at the dealerships with the 'free' oil changes and if you chose to pay more, synthetic in 5w30 as well since this appears to be the bulk grade. But why would they also offer a recommendation for the 40 grade and qualify it with the 'for improved vehicle performance' phrase?
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I don't even know what obfuscate means. I'd have to use my browser dictionary if I wanted to know.
"Engine oil viscosity (thickness) has an effect on fuel economy and cold weather operating ................................... however, higher viscosity engine oils are required for satisfactory lubrication in hot weather. .......................
When choosing an oil, consider the range of temperature your vehicle will be operated in before the next oil change. Proceed to select the recommended oil viscosity from the chart."
Fair common sense statements made and gives everyone room to move. It's quite clear higher viscosity is recommended in hotter climates with hot weather. It follows then if the vehicle if driven under extreme conditions and always running hot then high viscosity would also makes sense.
When choosing an oil, consider the range of temperature your vehicle will be operated in before the next oil change. Proceed to select the recommended oil viscosity from the chart."
Fair common sense statements made and gives everyone room to move. It's quite clear higher viscosity is recommended in hotter climates with hot weather. It follows then if the vehicle if driven under extreme conditions and always running hot then high viscosity would also makes sense.
It DOES follow common (and engineering sense)...some people would rather the manufacturers neuter the engine, even when operated entirely within the performance envelope of the OEM design than accept that hotter oil temperatures demand higher viscosity, and higher viscosity provides greater component separation distances.
wemay
Site Donor 2023
Originally Posted By: aquariuscsm
Straight from Hyundai. Thinner for fuel economy,thicker for protection. Go with the 5W40.
^
Straight from Hyundai. Thinner for fuel economy,thicker for protection. Go with the 5W40.
^
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Originally Posted By: Shannow
It DOES follow common (and engineering sense)...some people would rather the manufacturers neuter the engine, even when operated entirely within the performance envelope of the OEM design than accept that hotter oil temperatures demand higher viscosity, and higher viscosity provides greater component separation distances.
Which engines are being neutered and under what circumstances?
Is this a common occurrence?
If it's not really happening then the downsides of running thin oil while theoretically true, have no relevance in real world usage.
It DOES follow common (and engineering sense)...some people would rather the manufacturers neuter the engine, even when operated entirely within the performance envelope of the OEM design than accept that hotter oil temperatures demand higher viscosity, and higher viscosity provides greater component separation distances.
Which engines are being neutered and under what circumstances?
Is this a common occurrence?
If it's not really happening then the downsides of running thin oil while theoretically true, have no relevance in real world usage.
If you buy a car, and it's advertised, say, for it's performance. It's advertised as having a certain output, certain quarter mile times, top speeds etc.
And you drive it within it's factory programming and parameters, and without mechanical defect, would you expect it's cooling and lubrication systems to be able to handle it's advertised, and factory supplied performance ?
I would.
Do you consider the manufacturer neutering performance because the oil viscosity thins too much...within the supplied, factory envelope, as accaptable ?
I don't.
In the real world, you "don't need" even 100hp, whether you've paid for them or not...is that your point ?
And you drive it within it's factory programming and parameters, and without mechanical defect, would you expect it's cooling and lubrication systems to be able to handle it's advertised, and factory supplied performance ?
I would.
Do you consider the manufacturer neutering performance because the oil viscosity thins too much...within the supplied, factory envelope, as accaptable ?
I don't.
In the real world, you "don't need" even 100hp, whether you've paid for them or not...is that your point ?
Please consider as an example, the oft touted installation of an engine oil cooler to provide the margin for that brief "off chance" period when the engine out-drives it's oil.
$400-$500 of extra gear, for that "off chance", that you pay for the day you buy the car/install the gear.
Additional reliability issues (every complication to a design brings with it a reliability sacrifice...that's plain statistics).
Versus running the next grade up to counter the "off chance" that an engine would be used in it's design envelope...installation cost zero dollars, and zero cents...possibly even cost positive if you need unicorn tears as your baseline.
Next grade up will cost you maybe a "massive" 2% fuel consumption...over 100,000 miles, that's cost you 80 gallons (at 25MPG, YMMV)
But some will say that the extra viscosity will cost you horsepower...yes it will, not very much, and having the computer cut back your performance so that you don't do damage does so much more abruptly, and to much greater effect.
$400-$500 of extra gear, for that "off chance", that you pay for the day you buy the car/install the gear.
Additional reliability issues (every complication to a design brings with it a reliability sacrifice...that's plain statistics).
Versus running the next grade up to counter the "off chance" that an engine would be used in it's design envelope...installation cost zero dollars, and zero cents...possibly even cost positive if you need unicorn tears as your baseline.
Next grade up will cost you maybe a "massive" 2% fuel consumption...over 100,000 miles, that's cost you 80 gallons (at 25MPG, YMMV)
But some will say that the extra viscosity will cost you horsepower...yes it will, not very much, and having the computer cut back your performance so that you don't do damage does so much more abruptly, and to much greater effect.
No it isn't.
Using your logic, where do we draw the line? Even with a thicker oil there is a point where a vehicle needs to go into limp mode.
Performance vehicles running on thick oil are neutered when required too.
You've made a generic statement that thinner oil means you can't use the vehicle completely.
But are there any actual vehicles that this applies to that makes it a big deal? What circumstances will neuter them? How do those circumstances shift with one grade thicker oil and is that also unacceptable?
I don't dispute your theory. I just don't see how it applies to pretty much anyone who has purchased or is purchasing the vehicles out there that every year get more power yet slowly move to thinner oil.
Using your logic, where do we draw the line? Even with a thicker oil there is a point where a vehicle needs to go into limp mode.
Performance vehicles running on thick oil are neutered when required too.
You've made a generic statement that thinner oil means you can't use the vehicle completely.
But are there any actual vehicles that this applies to that makes it a big deal? What circumstances will neuter them? How do those circumstances shift with one grade thicker oil and is that also unacceptable?
I don't dispute your theory. I just don't see how it applies to pretty much anyone who has purchased or is purchasing the vehicles out there that every year get more power yet slowly move to thinner oil.
OVERKILL
$100 Site Donor 2021
Originally Posted By: Sam2000
But are there any actual vehicles that this applies to that makes it a big deal? What circumstances will neuter them? How do those circumstances shift with one grade thicker oil and is that also unacceptable?
I don't dispute your theory. I just don't see how it applies to pretty much anyone who has purchased or is purchasing the vehicles out there that every year get more power yet slowly move to thinner oil.
Yes, the Ford Mustang GT and the Nissan GT-R both succumb to "thermal castration" during use. The former spec's 5w-50, whilst it's "track pack" brother, with the same engine, spec's 5w-50 (like the BOSS 302, Ford GT, GT500...etc) and has a different castration temp.
There isn't the same scenario with the Nissan, but I believe some upgrade the oil cooler to get temps down to prevent it from happening.
But are there any actual vehicles that this applies to that makes it a big deal? What circumstances will neuter them? How do those circumstances shift with one grade thicker oil and is that also unacceptable?
I don't dispute your theory. I just don't see how it applies to pretty much anyone who has purchased or is purchasing the vehicles out there that every year get more power yet slowly move to thinner oil.
Yes, the Ford Mustang GT and the Nissan GT-R both succumb to "thermal castration" during use. The former spec's 5w-50, whilst it's "track pack" brother, with the same engine, spec's 5w-50 (like the BOSS 302, Ford GT, GT500...etc) and has a different castration temp.
There isn't the same scenario with the Nissan, but I believe some upgrade the oil cooler to get temps down to prevent it from happening.
Originally Posted By: wemay
CATERHAM said:But why would they also offer a recommendation for the 40 grade and qualify it with the 'for improved vehicle performance' phrase?
Drivers handbooks are not usually written by engineers and their choice of language is often poor, even misleading. A heavier oil grade does not improve engine performance in the slightest; quiet the contrary, it saps power and fuel economy. What it may do is possible reduce oil consumption under constant high rpm and high oil temp' usage so I guess you could consider that "improved performance".
The thing is both the 5W-30 and 5W-40 grades are recommended for unlimited maximum oil temp's. Here in NA it is the 5W-30 grade
that dealers use and of course running the 5W-30 grade, even a dino 5W-30, will not in any way void you warranty.
The engineers have set the engine management safety systems based on the lightest grade recommended which is 5W-30 consequently there is no lubrication benefit in running the heavier grade.
Originally Posted By: OVERKILL
Originally Posted By: Sam2000
But are there any actual vehicles that this applies to that makes it a big deal? What circumstances will neuter them? How do those circumstances shift with one grade thicker oil and is that also unacceptable?
I don't dispute your theory. I just don't see how it applies to pretty much anyone who has purchased or is purchasing the vehicles out there that every year get more power yet slowly move to thinner oil.
Yes, the Ford Mustang GT and the Nissan GT-R both succumb to "thermal castration" during use. The former spec's 5w-50, whilst it's "track pack" brother, with the same engine, spec's 5w-50 (like the BOSS 302, Ford GT, GT500...etc) and has a different castration temp.
There isn't the same scenario with the Nissan, but I believe some upgrade the oil cooler to get temps down to prevent it from happening.
So the Mustang seems to be an example that fits Shannows complaint.
But the GTR isn't. Add to the GTR the C63 AMG whose transmission goes into limp mode which was "fixed" on the Black Series by installing a larger cooler.
Limp modes abound in vehicles regardless of oil thickness, certainly they are on performance cars. Are they neutered because they are not running 60 or 70 weight instead of 40? Were Nissan wrong to develop the GTR with M1 0w40?
So far the Mustang is the only example given of a vehicle whose utility is reduced due to lighter oil spec and in that case it is going from a 50 to a 20.
There is zero evidence that going from 30 to 20 weight oil, which is the most common change that has happened, that vehicles have been neutered or are engaging neutering during usage. Sorry to say but on this forum too often a big complaint is made about a theoretical issue with no real life ramifications.
Originally Posted By: Sam2000
But are there any actual vehicles that this applies to that makes it a big deal? What circumstances will neuter them? How do those circumstances shift with one grade thicker oil and is that also unacceptable?
I don't dispute your theory. I just don't see how it applies to pretty much anyone who has purchased or is purchasing the vehicles out there that every year get more power yet slowly move to thinner oil.
Yes, the Ford Mustang GT and the Nissan GT-R both succumb to "thermal castration" during use. The former spec's 5w-50, whilst it's "track pack" brother, with the same engine, spec's 5w-50 (like the BOSS 302, Ford GT, GT500...etc) and has a different castration temp.
There isn't the same scenario with the Nissan, but I believe some upgrade the oil cooler to get temps down to prevent it from happening.
So the Mustang seems to be an example that fits Shannows complaint.
But the GTR isn't. Add to the GTR the C63 AMG whose transmission goes into limp mode which was "fixed" on the Black Series by installing a larger cooler.
Limp modes abound in vehicles regardless of oil thickness, certainly they are on performance cars. Are they neutered because they are not running 60 or 70 weight instead of 40? Were Nissan wrong to develop the GTR with M1 0w40?
So far the Mustang is the only example given of a vehicle whose utility is reduced due to lighter oil spec and in that case it is going from a 50 to a 20.
There is zero evidence that going from 30 to 20 weight oil, which is the most common change that has happened, that vehicles have been neutered or are engaging neutering during usage. Sorry to say but on this forum too often a big complaint is made about a theoretical issue with no real life ramifications.
wemay
Site Donor 2023
Correct me if im wrong but isnt the GT-R's limp mode attributed to the DCT overheating during track sessions and not the engine?
I understand what you're saying CATERHAM, my contention was with the reasoning behind the recommendation in the OM.
I understand what you're saying CATERHAM, my contention was with the reasoning behind the recommendation in the OM.
Originally Posted By: Sam2000
Originally Posted By: OVERKILL
Originally Posted By: Sam2000
But are there any actual vehicles that this applies to that makes it a big deal? What circumstances will neuter them? How do those circumstances shift with one grade thicker oil and is that also unacceptable?
I don't dispute your theory. I just don't see how it applies to pretty much anyone who has purchased or is purchasing the vehicles out there that every year get more power yet slowly move to thinner oil.
Yes, the Ford Mustang GT and the Nissan GT-R both succumb to "thermal castration" during use. The former spec's 5w-50, whilst it's "track pack" brother, with the same engine, spec's 5w-50 (like the BOSS 302, Ford GT, GT500...etc) and has a different castration temp.
There isn't the same scenario with the Nissan, but I believe some upgrade the oil cooler to get temps down to prevent it from happening.
So the Mustang seems to be an example that fits Shannows complaint.
But the GTR isn't. Add to the GTR the C63 AMG whose transmission goes into limp mode which was "fixed" on the Black Series by installing a larger cooler.
Limp modes abound in vehicles regardless of oil thickness, certainly they are on performance cars. Are they neutered because they are not running 60 or 70 weight instead of 40? Were Nissan wrong to develop the GTR with M1 0w40?
So far the Mustang is the only example given of a vehicle whose utility is reduced due to lighter oil spec and in that case it is going from a 50 to a 20.
There is zero evidence that going from 30 to 20 weight oil, which is the most common change that has happened, that vehicles have been neutered or are engaging neutering during usage. Sorry to say but on this forum too often a big complaint is made about a theoretical issue with no real life ramifications.
Referring the electronic safety systems that all modern cars now have in place as "thermal castration" is quite misleading.
Firstly, the bar (oil temp's) is set very high before the the safety systems will start to kick in. In the case of the 400+ hp Mustang GT that's spec'd for 5W-20 it's oil temp's north of 230F as a member found out at a track event and was unable to get his oil temp's high enough to trigger the safeties.
The reality is that the electronic safety systems are allowing the OEM's to maximize power, driveability and of course fuel economy by specifying a lighter oil grade.
The Mustang GT with the track pac' (and oil cooler) has the maximum oil temp's bar set much higher, hence the specified 5W-50 grade oil. Car has the same engine as the standard GT but it's will take some pretty extreme use under very high ambient temp's to benefit from the 50 grade oil. Anyone buying the track option for a primarily street driven car would be far better off running the 5W-20 grade.
Another example is the Subaru BRZ/Scion FR-S that's spec'd for the very light Toyota 0W-20. These cars don't come with oil coolers but they certainly could use them if you track the car on a hot day when oil temp's can reach 275F.
To survive those kind of oil temp's with such a light oil a very sophisticated ECU mapping safety system is in place. In fact most don't know it's working, that's how seamless it's operation is but there is an apparent torque reduction.
If there is a criticism of the manufacturer it shouldn't be that a heavier oil grade be specified, that is not the solution, but rather that the oil cooler should be standard fitment.
Originally Posted By: OVERKILL
Originally Posted By: Sam2000
But are there any actual vehicles that this applies to that makes it a big deal? What circumstances will neuter them? How do those circumstances shift with one grade thicker oil and is that also unacceptable?
I don't dispute your theory. I just don't see how it applies to pretty much anyone who has purchased or is purchasing the vehicles out there that every year get more power yet slowly move to thinner oil.
Yes, the Ford Mustang GT and the Nissan GT-R both succumb to "thermal castration" during use. The former spec's 5w-50, whilst it's "track pack" brother, with the same engine, spec's 5w-50 (like the BOSS 302, Ford GT, GT500...etc) and has a different castration temp.
There isn't the same scenario with the Nissan, but I believe some upgrade the oil cooler to get temps down to prevent it from happening.
So the Mustang seems to be an example that fits Shannows complaint.
But the GTR isn't. Add to the GTR the C63 AMG whose transmission goes into limp mode which was "fixed" on the Black Series by installing a larger cooler.
Limp modes abound in vehicles regardless of oil thickness, certainly they are on performance cars. Are they neutered because they are not running 60 or 70 weight instead of 40? Were Nissan wrong to develop the GTR with M1 0w40?
So far the Mustang is the only example given of a vehicle whose utility is reduced due to lighter oil spec and in that case it is going from a 50 to a 20.
There is zero evidence that going from 30 to 20 weight oil, which is the most common change that has happened, that vehicles have been neutered or are engaging neutering during usage. Sorry to say but on this forum too often a big complaint is made about a theoretical issue with no real life ramifications.
Referring the electronic safety systems that all modern cars now have in place as "thermal castration" is quite misleading.
Firstly, the bar (oil temp's) is set very high before the the safety systems will start to kick in. In the case of the 400+ hp Mustang GT that's spec'd for 5W-20 it's oil temp's north of 230F as a member found out at a track event and was unable to get his oil temp's high enough to trigger the safeties.
The reality is that the electronic safety systems are allowing the OEM's to maximize power, driveability and of course fuel economy by specifying a lighter oil grade.
The Mustang GT with the track pac' (and oil cooler) has the maximum oil temp's bar set much higher, hence the specified 5W-50 grade oil. Car has the same engine as the standard GT but it's will take some pretty extreme use under very high ambient temp's to benefit from the 50 grade oil. Anyone buying the track option for a primarily street driven car would be far better off running the 5W-20 grade.
Another example is the Subaru BRZ/Scion FR-S that's spec'd for the very light Toyota 0W-20. These cars don't come with oil coolers but they certainly could use them if you track the car on a hot day when oil temp's can reach 275F.
To survive those kind of oil temp's with such a light oil a very sophisticated ECU mapping safety system is in place. In fact most don't know it's working, that's how seamless it's operation is but there is an apparent torque reduction.
If there is a criticism of the manufacturer it shouldn't be that a heavier oil grade be specified, that is not the solution, but rather that the oil cooler should be standard fitment.
Operating any engine at an oil temp of around 300deg or greater is unacceptable and only should be done for short spurts. Thinking that a heavy oil makes things somehow hunky dory at that temp range is flawed.
Would we do the same thing to our transmissions? Run a thicker oil and think that makes it OK to run it at 350deg. I don't think so. You add extra cooling.
Would we do the same thing to our transmissions? Run a thicker oil and think that makes it OK to run it at 350deg. I don't think so. You add extra cooling.
Originally Posted By: turtlevette
Operating any engine at an oil temp of around 300deg or greater is unacceptable and only should be done for short spurts. Thinking that a heavy oil makes things somehow hunky dory at that temp range is flawed.
Would we do the same thing to our transmissions? Run a thicker oil and think that makes it OK to run it at 350deg. I don't think so. You add extra cooling.
Nobody @ our track would think 300-deg temps on their street or track cars is normal.Temps get that high,you've got cooling issues.Some of you have some strange thinking on these forums.
Operating any engine at an oil temp of around 300deg or greater is unacceptable and only should be done for short spurts. Thinking that a heavy oil makes things somehow hunky dory at that temp range is flawed.
Would we do the same thing to our transmissions? Run a thicker oil and think that makes it OK to run it at 350deg. I don't think so. You add extra cooling.
Nobody @ our track would think 300-deg temps on their street or track cars is normal.Temps get that high,you've got cooling issues.Some of you have some strange thinking on these forums.
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