Often on this site I read where some 40 weight oils are called a heavy 30 weight. Or used in a sentence "Mobil 1 0w40 is like a heavy 30 weight." What are people referring to or rather how do we tell that a 40 weight oil is like a heavy 30?
40 weights called heavy 30
- Thread starter Camprunner
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They are referring to the oil's viscosity at 100C. If an oil has a 100C viscosity that is just barely over the 40 grade minimum, some people will say it's like a heavy 30 grade.
That is because some oils like Mobil 1 0W40, are on the thin end of the scale of the viscosity required to classify as a SAE 40 engine oil.
Mobil 1 0W40 has a viscosity of 13.5cst at 100c, 40 grade engine oils go from 12.5 cst to 16.3, which makes it a thin 40 weight.
Usually 0W-XX engine oils are on the thin end of the scale, meanwhile 15W-XX and 20W-XX engine oils tend to be on the thicker end of the scale, also ILSAC GF-5 energy conserving oil tend to be on the thinner end of things.
Meanwhile ACEA A3/B4 oil which are meant for high performance cars tend to be on the thicker end.
Mobil 1 0W40 has a viscosity of 13.5cst at 100c, 40 grade engine oils go from 12.5 cst to 16.3, which makes it a thin 40 weight.
Usually 0W-XX engine oils are on the thin end of the scale, meanwhile 15W-XX and 20W-XX engine oils tend to be on the thicker end of the scale, also ILSAC GF-5 energy conserving oil tend to be on the thinner end of things.
Meanwhile ACEA A3/B4 oil which are meant for high performance cars tend to be on the thicker end.
Originally Posted By: FordCapriDriver
Mobil 1 0W40 has a viscosity of 13.5cst at 100c,
BTW, the stuff we get here in the US has a 100C viscosity of 12.9 cSt.
Mobil 1 0W40 has a viscosity of 13.5cst at 100c,
BTW, the stuff we get here in the US has a 100C viscosity of 12.9 cSt.
Originally Posted By: Camprunner
Often on this site I read where some 40 weight oils are called a heavy 30 weight. Or used in a sentence "Mobil 1 0w40 is like a heavy 30 weight." What are people referring to or rather how do we tell that a 40 weight oil is like a heavy 30?
Mobil 1 0W40 was known to shear down to 30 weight quickly. not sure if still the case.
Often on this site I read where some 40 weight oils are called a heavy 30 weight. Or used in a sentence "Mobil 1 0w40 is like a heavy 30 weight." What are people referring to or rather how do we tell that a 40 weight oil is like a heavy 30?
Mobil 1 0W40 was known to shear down to 30 weight quickly. not sure if still the case.
There has to be a line between 30 and 40 GRADE . An oil called a light 40 or a heavy 30 would be on the line OR BELOW after some miles and shearing. If you look at the SAE KV100 chart where grades are demarcated(viscosity at the temp of plain boiling water coolant), 12.5cSt is the margin between a heavy 30 and a light 40. I think more than a few 5w40 and 0w40 ACEA A3,B4 Porsche A40; MB 229.51 fit here.
Originally Posted By: Quattro Pete
Originally Posted By: FordCapriDriver
Mobil 1 0W40 has a viscosity of 13.5cst at 100c,
BTW, the stuff we get here in the US has a 100C viscosity of 12.9 cSt.
Really? but Mobil 1 0W40 being a 40 grade doesn't have to abide by ILSAC and GF-5 standards right?
Originally Posted By: FordCapriDriver
Mobil 1 0W40 has a viscosity of 13.5cst at 100c,
BTW, the stuff we get here in the US has a 100C viscosity of 12.9 cSt.
Really? but Mobil 1 0W40 being a 40 grade doesn't have to abide by ILSAC and GF-5 standards right?
Right.
There's more to it than kinematic viscosity, the 40 grades require a much higher minimum HTHSV too. So the heavy and light nomenclature is just something you'll see mostly on BITOG.
The truth is your engine can probably tolerate a wide range of viscosity and won't know the difference.
Think about how thick even a 0w20 will be in the cold and it is a much bigger difference than a 30 vs 40 grade at operating temperature.
The way we know if it's light or thick is by looking at the KV100 on the data sheet or voa and compare it to the viscosity chart.
Here is the sae j300 chart if you are curious and haven't seen it.
The truth is your engine can probably tolerate a wide range of viscosity and won't know the difference.
Think about how thick even a 0w20 will be in the cold and it is a much bigger difference than a 30 vs 40 grade at operating temperature.
The way we know if it's light or thick is by looking at the KV100 on the data sheet or voa and compare it to the viscosity chart.
Here is the sae j300 chart if you are curious and haven't seen it.
Look at HTHS, and measure of how well the oil behaves under high temperature and high shear loads
An ILSAC 30 grade has a HTHS of about 3.0 +/- 0.1 cP
However in Oz I can get a Euro grade Castrol EDGE 5W30 A3/B4 oil that has a HTHS of 3.6 cP
The new Mobil 1 0W40 FS has the same HTHS of 3.6 cP. This is the classic example of a thick 30 and a thin 40.
However in Oz GTX 15W40 has a HTHS of 4.0 cP. A thick 40.
Penrite 10-Tenths Racing 10W40 has a HTHS of 4.5 cP. A enormous 40.
M 1 5W50 has a HTHS of 4.4 cP, a thin 50.
In the old days of monogrades, as the KV100 went up, then so did the HTHS. The first was easy to measure, the second was important to protect the engine. So they sort of got tied together. However with VII and Multigrade oil you can increase the KV100 without much improvement in HTHS.
We need a new oil naming system, and I vote for the Shannow system
(winter start test)W-(HTHS x 10)
So Mobil 1 0W40 FS becomes Mobil 1 0W36
Castrol EDGE 5W40 becomes 5W38
Castrol EDGE 5W30 A3/B4 becomes 5W36
Mobil 1 5W30 GF-5 becomes 5W31
GTX 15W40 becomes GTX 15W40
Mobil 1 5W50 becomes Mobil 1 5W44
Etc
Then it's easy to compare oils.
An ILSAC 30 grade has a HTHS of about 3.0 +/- 0.1 cP
However in Oz I can get a Euro grade Castrol EDGE 5W30 A3/B4 oil that has a HTHS of 3.6 cP
The new Mobil 1 0W40 FS has the same HTHS of 3.6 cP. This is the classic example of a thick 30 and a thin 40.
However in Oz GTX 15W40 has a HTHS of 4.0 cP. A thick 40.
Penrite 10-Tenths Racing 10W40 has a HTHS of 4.5 cP. A enormous 40.
M 1 5W50 has a HTHS of 4.4 cP, a thin 50.
In the old days of monogrades, as the KV100 went up, then so did the HTHS. The first was easy to measure, the second was important to protect the engine. So they sort of got tied together. However with VII and Multigrade oil you can increase the KV100 without much improvement in HTHS.
We need a new oil naming system, and I vote for the Shannow system
(winter start test)W-(HTHS x 10)
So Mobil 1 0W40 FS becomes Mobil 1 0W36
Castrol EDGE 5W40 becomes 5W38
Castrol EDGE 5W30 A3/B4 becomes 5W36
Mobil 1 5W30 GF-5 becomes 5W31
GTX 15W40 becomes GTX 15W40
Mobil 1 5W50 becomes Mobil 1 5W44
Etc
Then it's easy to compare oils.
It's hair splitting, and was initially foisted by those with a certain bent...for example "Redline 5W20" is "REALLY a 5W30" is such a statement that was so prevalent that it became gospel to a certain group of fanbois.
The HTHS point is where it's at, period. That's what is protecting bearings, and is the primary cause of frag in pistons skirts.
SR5's monogrades are case in point of what an oil "naturally" should be, in it's unadulterated point.
http://www.technologylubricants.com/MSDS/CITGO/PDS/C500 single visc_pds.pdf
Code:
10W HTHS 2.3
20W20 HTHS 2.9
30 HTHS 3.6
40 HTHS 4.3
50 HTHS 5.1
J300 has MINIMUM HTHS for multigrades, which you can see from 901Memphis's posted chart.
Those with the certain bent that I described earlier are taking the HTHS MINIMUM, and using that to describe what an oil "really" is...
The 30s and 40s were an interesting anomoly in previous versions of J300 with the additive technology of years past. 0W, 5W, and 10W 40 only had an HTHS minimum of 2.9, just like the 30s...
The HTHS point is where it's at, period. That's what is protecting bearings, and is the primary cause of frag in pistons skirts.
SR5's monogrades are case in point of what an oil "naturally" should be, in it's unadulterated point.
http://www.technologylubricants.com/MSDS/CITGO/PDS/C500 single visc_pds.pdf
Code:
10W HTHS 2.3
20W20 HTHS 2.9
30 HTHS 3.6
40 HTHS 4.3
50 HTHS 5.1
J300 has MINIMUM HTHS for multigrades, which you can see from 901Memphis's posted chart.
Those with the certain bent that I described earlier are taking the HTHS MINIMUM, and using that to describe what an oil "really" is...
The 30s and 40s were an interesting anomoly in previous versions of J300 with the additive technology of years past. 0W, 5W, and 10W 40 only had an HTHS minimum of 2.9, just like the 30s...
Originally Posted By: SR5
However in Oz GTX 15W40 has a HTHS of 4.0 cP. A thick 40.
Penrite 10-Tenths Racing 10W40 has a HTHS of 4.5 cP. A enormous 40.
In light of Shannow's post above, it would seem both of these oils must be a fairly unadulterated 40-grade.
A lot of this "Thick 30, but really a thin 40" discussion comes from the European approved-oils circle, it seems. For example, one often sees reference to the BMW High Performance 5w30 oil being "thick enough to be a 5w-40."
Of course, if it were really that thick, it would be labelled as a 5w-40.
Furthermore, when it comes to the Euro approvals, the xW-40's are typically on the thinner end of that grade, while the xW-30's are on the thicker end. This is changing now with some of the newer "fuel economy" standards coming from the likes of Mercedes, BMW etc.
However in Oz GTX 15W40 has a HTHS of 4.0 cP. A thick 40.
Penrite 10-Tenths Racing 10W40 has a HTHS of 4.5 cP. A enormous 40.
In light of Shannow's post above, it would seem both of these oils must be a fairly unadulterated 40-grade.
A lot of this "Thick 30, but really a thin 40" discussion comes from the European approved-oils circle, it seems. For example, one often sees reference to the BMW High Performance 5w30 oil being "thick enough to be a 5w-40."
Of course, if it were really that thick, it would be labelled as a 5w-40.
Furthermore, when it comes to the Euro approvals, the xW-40's are typically on the thinner end of that grade, while the xW-30's are on the thicker end. This is changing now with some of the newer "fuel economy" standards coming from the likes of Mercedes, BMW etc.
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Shannow is right,saying Redline 5W20 is really a 5W30 is just plain asinine. It's a 5W20.
Originally Posted By: Shannow
It's hair splitting, and was initially foisted by those with a certain bent...for example "Redline 5W20" is "REALLY a 5W30" is such a statement that was so prevalent that it became gospel to a certain group of fanbois.
The HTHS point is where it's at, period. That's what is protecting bearings, and is the primary cause of frag in pistons skirts.
SR5's monogrades are case in point of what an oil "naturally" should be, in it's unadulterated point.
http://www.technologylubricants.com/MSDS/CITGO/PDS/C500 single visc_pds.pdf
Code:
10W HTHS 2.3
20W20 HTHS 2.9
30 HTHS 3.6
40 HTHS 4.3
50 HTHS 5.1
J300 has MINIMUM HTHS for multigrades, which you can see from 901Memphis's posted chart.
Those with the certain bent that I described earlier are taking the HTHS MINIMUM, and using that to describe what an oil "really" is...
The 30s and 40s were an interesting anomoly in previous versions of J300 with the additive technology of years past. 0W, 5W, and 10W 40 only had an HTHS minimum of 2.9, just like the 30s...
I think it was you or maybe it was somebody else that mentioned they fixed the 40 grades by making the minimum HTHS 3.5, but now they have to fix the 50 and 60 grades? i think you are right, in my opinion 50 grades should have a minimum HTHS of around 4.0, and 60 grades maybe 4.5, even though the grand majority of 50 grades already have a HTHS of 4 or more, and 60 grades have a HTHS of 5 or more.
It's hair splitting, and was initially foisted by those with a certain bent...for example "Redline 5W20" is "REALLY a 5W30" is such a statement that was so prevalent that it became gospel to a certain group of fanbois.
The HTHS point is where it's at, period. That's what is protecting bearings, and is the primary cause of frag in pistons skirts.
SR5's monogrades are case in point of what an oil "naturally" should be, in it's unadulterated point.
http://www.technologylubricants.com/MSDS/CITGO/PDS/C500 single visc_pds.pdf
Code:
10W HTHS 2.3
20W20 HTHS 2.9
30 HTHS 3.6
40 HTHS 4.3
50 HTHS 5.1
J300 has MINIMUM HTHS for multigrades, which you can see from 901Memphis's posted chart.
Those with the certain bent that I described earlier are taking the HTHS MINIMUM, and using that to describe what an oil "really" is...
The 30s and 40s were an interesting anomoly in previous versions of J300 with the additive technology of years past. 0W, 5W, and 10W 40 only had an HTHS minimum of 2.9, just like the 30s...
I think it was you or maybe it was somebody else that mentioned they fixed the 40 grades by making the minimum HTHS 3.5, but now they have to fix the 50 and 60 grades? i think you are right, in my opinion 50 grades should have a minimum HTHS of around 4.0, and 60 grades maybe 4.5, even though the grand majority of 50 grades already have a HTHS of 4 or more, and 60 grades have a HTHS of 5 or more.
Originally Posted By: Shannow
the system is broken.
When they get to "x"W HTHS, instead of the J300 grades, I will have won
They will fix that right after they fix crime, drugs and the hospital system.
To be honest, it's the easiest and cheapest on the list to fix. Just not on enough people's radar. People who change their own oil are few and far between.
the system is broken.
When they get to "x"W HTHS, instead of the J300 grades, I will have won
They will fix that right after they fix crime, drugs and the hospital system.
To be honest, it's the easiest and cheapest on the list to fix. Just not on enough people's radar. People who change their own oil are few and far between.
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And 99% of those people who change their own oil, probably know nothing about engine oils other than viscosity grades, and if what they use is synthetic or mineral, those of us who actually look at HTHS, TBN, Viscodity Index and so on are an incredibly small minority.
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