Originally Posted By: Shannow
In Shannow's ideal world, the ratings would be changed to xW - HTHS
I'd like that, as well.
In Shannow's ideal world, the ratings would be changed to xW - HTHS
I'd like that, as well.
Multi-weight oil gets thicker or thinner?
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OVERKILL
$100 Site Donor 2021
Originally Posted By: aquariuscsm
A viscosity comparison I see all the time that is completely false is that for example a 5W50 and mono grade 50 are the exact same viscosity once at operating temp. This is completely false. Use both and drain hot. The 5W50 is like water compared to a mono grade 50.
If the 5w-50 has the same 100C visc as the SAE50 then they are the same viscosity, you saying they are not doesn't magically change the science. Are you draining oil that is 100C (212F) from your sump?
The more likely scenario is that one, another, or both of these scenarios are happening:
1. The oil is not at 100C, and since a 5w-50 will have a much higher VI than a SAE50 the SAE50 will be significantly thicker below 100C than the 5w-50.
2. The SAE50 is probably not the same viscosity as the 5w-50, since the "50" represents a RANGE of viscosities from 16.3 to 21.9cSt.
A viscosity comparison I see all the time that is completely false is that for example a 5W50 and mono grade 50 are the exact same viscosity once at operating temp. This is completely false. Use both and drain hot. The 5W50 is like water compared to a mono grade 50.
If the 5w-50 has the same 100C visc as the SAE50 then they are the same viscosity, you saying they are not doesn't magically change the science. Are you draining oil that is 100C (212F) from your sump?
The more likely scenario is that one, another, or both of these scenarios are happening:
1. The oil is not at 100C, and since a 5w-50 will have a much higher VI than a SAE50 the SAE50 will be significantly thicker below 100C than the 5w-50.
2. The SAE50 is probably not the same viscosity as the 5w-50, since the "50" represents a RANGE of viscosities from 16.3 to 21.9cSt.
Originally Posted By: OVERKILL
Originally Posted By: aquariuscsm
A viscosity comparison I see all the time that is completely false is that for example a 5W50 and mono grade 50 are the exact same viscosity once at operating temp. This is completely false. Use both and drain hot. The 5W50 is like water compared to a mono grade 50.
If the 5w-50 has the same 100C visc as the SAE50 then they are the same viscosity, you saying they are not doesn't magically change the science. Are you draining oil that is 100C (212F) from your sump?
The more likely scenario is that one, another, or both of these scenarios are happening:
1. The oil is not at 100C, and since a 5w-50 will have a much higher VI than a SAE50 the SAE50 will be significantly thicker below 100C than the 5w-50.
2. The SAE50 is probably not the same viscosity as the 5w-50, since the "50" represents a RANGE of viscosities from 16.3 to 21.9cSt.
I would guess the oil was below 100C, as 60/65C is already 'burning' to touch.
Originally Posted By: aquariuscsm
A viscosity comparison I see all the time that is completely false is that for example a 5W50 and mono grade 50 are the exact same viscosity once at operating temp. This is completely false. Use both and drain hot. The 5W50 is like water compared to a mono grade 50.
If the 5w-50 has the same 100C visc as the SAE50 then they are the same viscosity, you saying they are not doesn't magically change the science. Are you draining oil that is 100C (212F) from your sump?
The more likely scenario is that one, another, or both of these scenarios are happening:
1. The oil is not at 100C, and since a 5w-50 will have a much higher VI than a SAE50 the SAE50 will be significantly thicker below 100C than the 5w-50.
2. The SAE50 is probably not the same viscosity as the 5w-50, since the "50" represents a RANGE of viscosities from 16.3 to 21.9cSt.
I would guess the oil was below 100C, as 60/65C is already 'burning' to touch.
Originally Posted By: aquariuscsm
Use both and drain hot. The 5W50 is like water compared to a mono grade 50.
They're still both within the range of an SAE 50, though. The SAE 50 monograde may have higher HTHS and higher KV than the 5w-50, and that would be readily apparent on data sheets and in various tests.
Look at it this way. An ILSAC 5w-30 should be lower in KV 100 and HTHS than a monograde 30. I bet GC 0w-30, at operating temperatures, would much more closely resemble an SAE 30 monograde.
Use both and drain hot. The 5W50 is like water compared to a mono grade 50.
They're still both within the range of an SAE 50, though. The SAE 50 monograde may have higher HTHS and higher KV than the 5w-50, and that would be readily apparent on data sheets and in various tests.
Look at it this way. An ILSAC 5w-30 should be lower in KV 100 and HTHS than a monograde 30. I bet GC 0w-30, at operating temperatures, would much more closely resemble an SAE 30 monograde.
I don't want "range" - I want absolute
I want Shannow's system
I want Shannow's system
Well, range is all you get.
With what we have in North America, you can usually guess that HTHS of most lubricants +/- 0.1 of the actual value, by virtue of the specifications alone. Find me an ILSAC 0w-30, 5w-30, or 10w-30 that isn't between 2.9 and 3.2, or an A3/B4 30 or 40 that isn't at 3.5 to 3.7.
Of course, the ones we get really curious about, like certain uncertified boutiques, are the ones that don't give us the information!
Of course, the ones we get really curious about, like certain uncertified boutiques, are the ones that don't give us the information!
Originally Posted By: Quattro Pete
Originally Posted By: Shannow
In Shannow's ideal world, the ratings would be changed to xW - HTHS
I'd like that, as well.
Yes, I too vote for this system. Even if it operates in parallel with the old system during a change over period.
Originally Posted By: Shannow
In Shannow's ideal world, the ratings would be changed to xW - HTHS
I'd like that, as well.
Yes, I too vote for this system. Even if it operates in parallel with the old system during a change over period.
Originally Posted By: SR5
Originally Posted By: Quattro Pete
Originally Posted By: Shannow
In Shannow's ideal world, the ratings would be changed to xW - HTHS
I'd like that, as well.
Yes, I too vote for this system. Even if it operates in parallel with the old system during a change over period.
Could you imagine the freak out from the average auto owner? They'd lose it seeing 0w-2.6. Try telling someone that has an older car that they should be using 5w-2.9 to 5w-3.5 instead of 5w-30. They'd think you were telling them to intentionally destroy their engine.
I agree though, this would be a meaningful spec for us in the know on motor oils.
Originally Posted By: Quattro Pete
Originally Posted By: Shannow
In Shannow's ideal world, the ratings would be changed to xW - HTHS
I'd like that, as well.
Yes, I too vote for this system. Even if it operates in parallel with the old system during a change over period.
Could you imagine the freak out from the average auto owner? They'd lose it seeing 0w-2.6. Try telling someone that has an older car that they should be using 5w-2.9 to 5w-3.5 instead of 5w-30. They'd think you were telling them to intentionally destroy their engine.
I agree though, this would be a meaningful spec for us in the know on motor oils.
Shannow:
The 50s and 60s share the same 3.7HTHS minimum
This really needs to be fixed up, that's way to low for 50 and 60 grade oil.
Even 40 grade is wide enough:
M1 0W-40 new = 3.6
M1 0W-40 old = 3.8
GTX 15W-40 = 3.95
Then you have
M1 5W-50 = 4.4
M1 15W-50 = 4.5
Surely 50 grade oil should have a min HTHS of about 4.0
Not too sure about 60 grade oil
Edge 10W-60 = 5.1
Edge 25W-50 = 6.1
But I've always heard that Edge 10W-60 is really more of a 50 grade oil.
Doesn't Penrite Racing 10W-40 have a HTHS of about 4.5 ? (from memory).
The thick end of J300 is a bit of a mess.
The 50s and 60s share the same 3.7HTHS minimum
This really needs to be fixed up, that's way to low for 50 and 60 grade oil.
Even 40 grade is wide enough:
M1 0W-40 new = 3.6
M1 0W-40 old = 3.8
GTX 15W-40 = 3.95
Then you have
M1 5W-50 = 4.4
M1 15W-50 = 4.5
Surely 50 grade oil should have a min HTHS of about 4.0
Not too sure about 60 grade oil
Edge 10W-60 = 5.1
Edge 25W-50 = 6.1
But I've always heard that Edge 10W-60 is really more of a 50 grade oil.
Doesn't Penrite Racing 10W-40 have a HTHS of about 4.5 ? (from memory).
The thick end of J300 is a bit of a mess.
Originally Posted By: Torrid
Originally Posted By: Shannow
In Shannow's ideal world, the ratings would be changed to xW - HTHS
Could you imagine the freak out from the average auto owner? They'd lose it seeing 0w-2.6. Try telling someone that has an older car that they should be using 5w-2.9 to 5w-3.5 instead of 5w-30. They'd think you were telling them to intentionally destroy their engine.
I agree though, this would be a meaningful spec for us in the know on motor oils.
Good point, how about this ? We use: xW - (HTHS x 10)
That way the average ILSAC 5W-30 with a HTHS of 3.0 would end up being, 5W-30 !!!
Sure, some would be 5W-29 and others 5W-31, but most people should be able to deal with this.
My Edge 5W-30 A3/B4 would become Edge 5W-36, nice !!
Originally Posted By: Shannow
In Shannow's ideal world, the ratings would be changed to xW - HTHS
Could you imagine the freak out from the average auto owner? They'd lose it seeing 0w-2.6. Try telling someone that has an older car that they should be using 5w-2.9 to 5w-3.5 instead of 5w-30. They'd think you were telling them to intentionally destroy their engine.
I agree though, this would be a meaningful spec for us in the know on motor oils.
Good point, how about this ? We use: xW - (HTHS x 10)
That way the average ILSAC 5W-30 with a HTHS of 3.0 would end up being, 5W-30 !!!
Sure, some would be 5W-29 and others 5W-31, but most people should be able to deal with this.
My Edge 5W-30 A3/B4 would become Edge 5W-36, nice !!
If we use: xW - (HTHS x 10) and round to two figures
M1 0W-40 new = 3.6 becomes M1 0W-36
M1 0W-40 old = 3.8 becomes M1 0W-38
GTX 15W-40 = 3.95 becomes GTX 15W-40
M1 5W-50 = 4.4 becomes M1 5W-44
M1 15W-50 = 4.5 becomes M1 15W-45
Edge 10W-60 = 5.1 becomes Edge 10W-51
Edge 25W-50 = 6.1 becomes Edge 25W-61
Ahhhh that's better.
M1 0W-40 new = 3.6 becomes M1 0W-36
M1 0W-40 old = 3.8 becomes M1 0W-38
GTX 15W-40 = 3.95 becomes GTX 15W-40
M1 5W-50 = 4.4 becomes M1 5W-44
M1 15W-50 = 4.5 becomes M1 15W-45
Edge 10W-60 = 5.1 becomes Edge 10W-51
Edge 25W-50 = 6.1 becomes Edge 25W-61
Ahhhh that's better.
I can work with that SR5.
Mobil 1 V-Twin 20W50 becomes 20W-62
Mobil 1 Racing 0W50 becomes 0W-38 (silly unicorn that it is).
I agree with your comments on 50s and 60s at 3.7, because it drives exactly those behaviours that lead to the M1 Racing 0W50.
People buy "50" thinking it's "50", when the HTHS is 40 grade.
Mobil 1 V-Twin 20W50 becomes 20W-62
Mobil 1 Racing 0W50 becomes 0W-38 (silly unicorn that it is).
I agree with your comments on 50s and 60s at 3.7, because it drives exactly those behaviours that lead to the M1 Racing 0W50.
People buy "50" thinking it's "50", when the HTHS is 40 grade.
I like it
But to the OP's question - the viscosity improvers or viscosity modifiers in multi-grades means that as the oil heats up, it thins more slowly than a single weight. AT 100* the viscosity equals a thicker single weight.
If you plotted an oil thinning out as it gets hotter, the multi's would have a less steep slope than the single weights
But to the OP's question - the viscosity improvers or viscosity modifiers in multi-grades means that as the oil heats up, it thins more slowly than a single weight. AT 100* the viscosity equals a thicker single weight.
If you plotted an oil thinning out as it gets hotter, the multi's would have a less steep slope than the single weights
Last edited:
Originally Posted By: SR5
If we use: xW - (HTHS x 10) and round to two figures
M1 0W-40 new = 3.6 becomes M1 0W-36
M1 0W-40 old = 3.8 becomes M1 0W-38
GTX 15W-40 = 3.95 becomes GTX 15W-40
M1 5W-50 = 4.4 becomes M1 5W-44
M1 15W-50 = 4.5 becomes M1 15W-45
Edge 10W-60 = 5.1 becomes Edge 10W-51
Edge 25W-50 = 6.1 becomes Edge 25W-61
Ahhhh that's better.
I hadn't thought of applying x10. That actually works really well.
If we use: xW - (HTHS x 10) and round to two figures
M1 0W-40 new = 3.6 becomes M1 0W-36
M1 0W-40 old = 3.8 becomes M1 0W-38
GTX 15W-40 = 3.95 becomes GTX 15W-40
M1 5W-50 = 4.4 becomes M1 5W-44
M1 15W-50 = 4.5 becomes M1 15W-45
Edge 10W-60 = 5.1 becomes Edge 10W-51
Edge 25W-50 = 6.1 becomes Edge 25W-61
Ahhhh that's better.
I hadn't thought of applying x10. That actually works really well.
Originally Posted By: Torrid
Could you imagine the freak out from the average auto owner? They'd lose it seeing 0w-2.6. Try telling someone that has an older car that they should be using 5w-2.9 to 5w-3.5 instead of 5w-30. They'd think you were telling them to intentionally destroy their engine.
Of course they would! At least they could publish HTHS on more data sheets or on the bottle somewhere.
Could you imagine the freak out from the average auto owner? They'd lose it seeing 0w-2.6. Try telling someone that has an older car that they should be using 5w-2.9 to 5w-3.5 instead of 5w-30. They'd think you were telling them to intentionally destroy their engine.
Of course they would! At least they could publish HTHS on more data sheets or on the bottle somewhere.
Originally Posted By: Torrid
Originally Posted By: SR5
If we use: xW - (HTHS x 10) and round to two figures
I hadn't thought of applying x10. That actually works really well.
I know ! It's quite surprising.
Not only does it sort out the silly ones
Originally Posted By: SR5
Edge 10W-60 = 5.1 becomes Edge 10W-51
Edge 25W-50 = 6.1 becomes Edge 25W-61
Originally Posted By: Shannow
Mobil 1 V-Twin 20W50 becomes 20W-62
Mobil 1 Racing 0W50 becomes 0W-38 (silly unicorn that it is).
It's also interesting to see what stays the same.
Castrol GTX 15W-40 becomes 15W-40
Kendall GT-1 5W-30 becomes 5W-30
M1 AFE 0W-30 becomes 0W-30
M1 EP 5W-30 becomes 5W-30
M1 10W-30 becomes 10W-30
I'll also give a honourable mention to
M1 HM 10W-40 becomes 10W-39
Penrite HPR 30 (20W-60) becomes 20W-62 (that's a stout oil)
And these xW-20 oils are really xW-27 or xW-28 oils. Suddenly they don't look as thin as they sound.
Originally Posted By: SR5
If we use: xW - (HTHS x 10) and round to two figures
I hadn't thought of applying x10. That actually works really well.
I know ! It's quite surprising.
Not only does it sort out the silly ones
Originally Posted By: SR5
Edge 10W-60 = 5.1 becomes Edge 10W-51
Edge 25W-50 = 6.1 becomes Edge 25W-61
Originally Posted By: Shannow
Mobil 1 V-Twin 20W50 becomes 20W-62
Mobil 1 Racing 0W50 becomes 0W-38 (silly unicorn that it is).
It's also interesting to see what stays the same.
Castrol GTX 15W-40 becomes 15W-40
Kendall GT-1 5W-30 becomes 5W-30
M1 AFE 0W-30 becomes 0W-30
M1 EP 5W-30 becomes 5W-30
M1 10W-30 becomes 10W-30
I'll also give a honourable mention to
M1 HM 10W-40 becomes 10W-39
Penrite HPR 30 (20W-60) becomes 20W-62 (that's a stout oil)
And these xW-20 oils are really xW-27 or xW-28 oils. Suddenly they don't look as thin as they sound.
Originally Posted By: Quartz
Originally Posted By: aquariuscsm
A viscosity comparison I see all the time that is completely false is that for example a 5W50 and mono grade 50 are the exact same viscosity once at operating temp. This is completely false. Use both and drain hot. The 5W50 is like water compared to a mono grade 50.
Yeah, this is something my mechanic pointed out and one of the reasons I decided to ask how this works. If the -50 doesn't actually represent what a straight 50 would be, what DOES it represent?
some kind of device that measures the flow at given temperatures.
Originally Posted By: aquariuscsm
A viscosity comparison I see all the time that is completely false is that for example a 5W50 and mono grade 50 are the exact same viscosity once at operating temp. This is completely false. Use both and drain hot. The 5W50 is like water compared to a mono grade 50.
Yeah, this is something my mechanic pointed out and one of the reasons I decided to ask how this works. If the -50 doesn't actually represent what a straight 50 would be, what DOES it represent?
some kind of device that measures the flow at given temperatures.
OVERKILL
$100 Site Donor 2021
Originally Posted By: CT8
What would be interesting is the difference of the viscosity between the metals with a straight 50 vs a 5W-50
That's what HTHS tells you.
What would be interesting is the difference of the viscosity between the metals with a straight 50 vs a 5W-50
That's what HTHS tells you.
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