I mixed 5 quarts M1 0W20 with 2 quarts M1 0W40 and 6 oz VSOT, the end result is a heavy 0W30 with high 170's VI and around 3.1-3.2 HTHS. The E430 ran very smooth with the mix.
HTHS Question
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Originally Posted By: lemonade
Originally Posted By: Gokhan
Originally Posted By: mechtech2
OK then. 0 Zero in HTHS engine oil terms is not water's viscosity, but more of an absolute zero viscosity.
A total vacuum would be a zero HTHS, for instance.
[I don't think those who set the parameters had superfluids or total vacuum engine operation in mind}
Yes, water has nonzero viscosity, and so do all normal fluids.
Not sure what you mean by "0 Zero in HTHS engine-oil terms" but viscosity (dynamic as in HTHS or kinematic) is not just an engine-oil term but a more general physical quantity used for all fluids. Also, as you know, of course, 0W in SAE 0W-x grades is not a measure of viscosity but only some cold-temperature viscosity-grade specification. NLGI also uses 0, 00, 000, etc. for the thinner grease grades.
The only fluids in nature that have zero viscosity are superfluids. In fact, the only known superfluid is liquid helium near the absolute zero temperature, less than 2 degrees kelvin above absolute zero for the abundant He-4 isotope of helium. It becomes a normal fluid at higher temperatures and boils around 4 degrees kelvin above absolute zero. Less abundant He-3 isotope also exhibits superfluidity but at even much lower temperatures and due to a different physical mechanism.
I guess you can talk about the viscosity of vacuum if you really want to but since vacuum means absence of matter, it's not really a fluid, and it would be hard to define and/or devise a method to measure its viscosity. It would also strongly depend on the vacuum pressure of course.
Unlike a superfluid, the viscosity of vacuum would also never be exactly zero. If you consider the ideal case of an exact vacuum, then you can't talk about viscosity because there is no fluid (matter). On the other hand, superfluid helium has absolute zero viscosity because of a subtle quantum mechanism. It can do a lot of interesting things. For example if you put superfluid helium in a cup, it creeps up along the inside wall and then down the outside wall until the cup is completely empty. See this picture of superfluid helium in a cup:
So, if you could refrigerate your garage to near absolute-zero temperature and put superfluid helium in your engine, thanks to having absolute zero viscosity, it would creep up your dipstick tube and you would find it all on the floor when you came back in the evening.
Remind me of quantum class, He, with 2 proton, 2 neutron and 2 electron, He-4 is a boson, hence subject to Bose-einstein statistics, and boson are not subject to Pauli exclusion principle, so there's no limit to the number of bosons that may be in the same quantum state, so we have superfluid. oh my god, can't believe i still remember these.
Oh, about He-4 flow up the dipstick thing, this is called "creeping flim", i think... don't remember exactly.
I have something to add about liquid He though, if one tries to measure the viscosity by, for example, measuring the drag on a metal plate as it is passed over the surface of the liquid, the result is about the same as the one we would expect from a normal liquid, even at temperatuire below the lambda point. Inother word, there appears to be a contradiction here. Some scientist later proposed a solution stating that liquid He below lambda point is part superfluid and part normal, with increasing portion of superfluid approaching 0Kelvin once it drop below lambda point.
Way off topic.... sorry
Ah, another physicist here! Cool!
Good knowledge by the way.
Originally Posted By: Gokhan
Originally Posted By: mechtech2
OK then. 0 Zero in HTHS engine oil terms is not water's viscosity, but more of an absolute zero viscosity.
A total vacuum would be a zero HTHS, for instance.
[I don't think those who set the parameters had superfluids or total vacuum engine operation in mind}
Yes, water has nonzero viscosity, and so do all normal fluids.
Not sure what you mean by "0 Zero in HTHS engine-oil terms" but viscosity (dynamic as in HTHS or kinematic) is not just an engine-oil term but a more general physical quantity used for all fluids. Also, as you know, of course, 0W in SAE 0W-x grades is not a measure of viscosity but only some cold-temperature viscosity-grade specification. NLGI also uses 0, 00, 000, etc. for the thinner grease grades.
The only fluids in nature that have zero viscosity are superfluids. In fact, the only known superfluid is liquid helium near the absolute zero temperature, less than 2 degrees kelvin above absolute zero for the abundant He-4 isotope of helium. It becomes a normal fluid at higher temperatures and boils around 4 degrees kelvin above absolute zero. Less abundant He-3 isotope also exhibits superfluidity but at even much lower temperatures and due to a different physical mechanism.
I guess you can talk about the viscosity of vacuum if you really want to but since vacuum means absence of matter, it's not really a fluid, and it would be hard to define and/or devise a method to measure its viscosity. It would also strongly depend on the vacuum pressure of course.
Unlike a superfluid, the viscosity of vacuum would also never be exactly zero. If you consider the ideal case of an exact vacuum, then you can't talk about viscosity because there is no fluid (matter). On the other hand, superfluid helium has absolute zero viscosity because of a subtle quantum mechanism. It can do a lot of interesting things. For example if you put superfluid helium in a cup, it creeps up along the inside wall and then down the outside wall until the cup is completely empty. See this picture of superfluid helium in a cup:
So, if you could refrigerate your garage to near absolute-zero temperature and put superfluid helium in your engine, thanks to having absolute zero viscosity, it would creep up your dipstick tube and you would find it all on the floor when you came back in the evening.
Remind me of quantum class, He, with 2 proton, 2 neutron and 2 electron, He-4 is a boson, hence subject to Bose-einstein statistics, and boson are not subject to Pauli exclusion principle, so there's no limit to the number of bosons that may be in the same quantum state, so we have superfluid. oh my god, can't believe i still remember these.
Oh, about He-4 flow up the dipstick thing, this is called "creeping flim", i think... don't remember exactly.
I have something to add about liquid He though, if one tries to measure the viscosity by, for example, measuring the drag on a metal plate as it is passed over the surface of the liquid, the result is about the same as the one we would expect from a normal liquid, even at temperatuire below the lambda point. Inother word, there appears to be a contradiction here. Some scientist later proposed a solution stating that liquid He below lambda point is part superfluid and part normal, with increasing portion of superfluid approaching 0Kelvin once it drop below lambda point.
Way off topic.... sorry
Ah, another physicist here! Cool!
Originally Posted By: KCJeep
Originally Posted By: Gokhan
Originally Posted By: KCJeep
Great thread!
I can't understand all of it but HTHS intrigues me as a habitual blender. Lately I've been focused more on HTHS in my blends, but I don't really know how to calculate it. If you say it's linear will a simple average using accurate percentages work?
My Jeep is spec'd for 10w30, most PCMO of which are around 3.0 to 3.1 HTHS. It runs fantastic though on 5w30 of 2.9 to 3.0 HTHS. I am however afraid to use 5W30 in the summer due to shear concerns. I've recently found several 5w30 High Mileage oils with HTHS in the 3.2 to 3.3 range, so I'm thinking there is absolutely no reason not to run those in the warm months. They have higher VI and a higher HTHS than many 10w30's.
Am I correct in my thinking here? If so why on earth would I run a 10w30 ever?
I wouldn't worry much about permanent oil shear with a synthetic 5W-30. A conventional 5W-30 shears quite a bit a synthetic 5W-30 not so much. Therefore, I think a synthetic 5W-30 would always be an excellent replacement for a conventional 10W-30, which some conventional-oil users prefer over conventional 5W-30 because of shear stability.
Thank you, I don't use synthetics but a couple of the HM oils I mentioned are syn blends, I'd think those okay then since I don't do long OCI's due to warranty?
Well, it also depends on your engine how thin it can tolerate. I wouldn't worry about it too much. You can always do a UOA to see how much the oil sheared. It can also give you an idea on the condition of the engine. Using a fully synthetic oil could give you an extra peace of mind. There are quality but cheap oils like Formula Shell fully synthetic and also most major-brand synthetics go on periodic sales.
At the end, it might not make a difference at all conventional or synthetic.
As far as the manufacturer's recommendations are concerned, I tend to believe that recommendation of 10W-30 instead of 5W-30 has more to do with the quality of earlier-API-grade 5W-30s than the oil shear. 10W-30 instead of 5W-30 was recommended very often by many manufacturers in the past. I believe, in the past, the viscosity-index improvers were of poor quality and they tended to not only shear too much but cause deposits as well. (They are plastics after all.) I think with modern ILSAC GF-4 and GF-5 or API SM or SN oils, such concerns are no longer major. Chances are that if Jeep made the recommendation for the same engine today, they would recommend a 5W-30.
Note that at some point in the past GM (?) recommended against 10W-40 because of large amounts of viscosity-index improvers used in conventional 10W-40 that allegedly lead to oil-deposit-related engine damage.
In summary, I think you would be OK with any conventional or synthetic xW-30 but you would see the least engine deposits and longest oil life with a quality fully synthetic xW-30.
Originally Posted By: Gokhan
Originally Posted By: KCJeep
Great thread!
I can't understand all of it but HTHS intrigues me as a habitual blender. Lately I've been focused more on HTHS in my blends, but I don't really know how to calculate it. If you say it's linear will a simple average using accurate percentages work?
My Jeep is spec'd for 10w30, most PCMO of which are around 3.0 to 3.1 HTHS. It runs fantastic though on 5w30 of 2.9 to 3.0 HTHS. I am however afraid to use 5W30 in the summer due to shear concerns. I've recently found several 5w30 High Mileage oils with HTHS in the 3.2 to 3.3 range, so I'm thinking there is absolutely no reason not to run those in the warm months. They have higher VI and a higher HTHS than many 10w30's.
Am I correct in my thinking here? If so why on earth would I run a 10w30 ever?
I wouldn't worry much about permanent oil shear with a synthetic 5W-30. A conventional 5W-30 shears quite a bit a synthetic 5W-30 not so much. Therefore, I think a synthetic 5W-30 would always be an excellent replacement for a conventional 10W-30, which some conventional-oil users prefer over conventional 5W-30 because of shear stability.
Thank you, I don't use synthetics but a couple of the HM oils I mentioned are syn blends, I'd think those okay then since I don't do long OCI's due to warranty?
Well, it also depends on your engine how thin it can tolerate. I wouldn't worry about it too much. You can always do a UOA to see how much the oil sheared. It can also give you an idea on the condition of the engine. Using a fully synthetic oil could give you an extra peace of mind. There are quality but cheap oils like Formula Shell fully synthetic and also most major-brand synthetics go on periodic sales.
At the end, it might not make a difference at all conventional or synthetic.
As far as the manufacturer's recommendations are concerned, I tend to believe that recommendation of 10W-30 instead of 5W-30 has more to do with the quality of earlier-API-grade 5W-30s than the oil shear. 10W-30 instead of 5W-30 was recommended very often by many manufacturers in the past. I believe, in the past, the viscosity-index improvers were of poor quality and they tended to not only shear too much but cause deposits as well. (They are plastics after all.) I think with modern ILSAC GF-4 and GF-5 or API SM or SN oils, such concerns are no longer major. Chances are that if Jeep made the recommendation for the same engine today, they would recommend a 5W-30.
Note that at some point in the past GM (?) recommended against 10W-40 because of large amounts of viscosity-index improvers used in conventional 10W-40 that allegedly lead to oil-deposit-related engine damage.
In summary, I think you would be OK with any conventional or synthetic xW-30 but you would see the least engine deposits and longest oil life with a quality fully synthetic xW-30.
Originally Posted By: KCJeep
Lately I've been focused more on HTHS in my blends, but I don't really know how to calculate it. If you say it's linear will a simple average using accurate percentages work?
For blending, viscosity blends on a log/linear scale. If the viscosities are close, a linear calculation will be close enough.
Tom NJ
Lately I've been focused more on HTHS in my blends, but I don't really know how to calculate it. If you say it's linear will a simple average using accurate percentages work?
For blending, viscosity blends on a log/linear scale. If the viscosities are close, a linear calculation will be close enough.
Tom NJ
Originally Posted By: Gokhan
As far as the manufacturer's recommendations are concerned, I tend to believe that recommendation of 10W-30 instead of 5W-30 has more to do with the quality of earlier-API-grade 5W-30s than the oil shear. 10W-30 instead of 5W-30 was recommended very often by many manufacturers in the past. I believe, in the past, the viscosity-index improvers were of poor quality and they tended to not only shear too much but cause deposits as well. (They are plastics after all.) I think with modern ILSAC GF-4 and GF-5 or API SM or SN oils, such concerns are no longer major.
These days, the best reason to use a 10w-30 would be for a conventional HDEO. Conventional 5w-30s are definitely better now than they used to be.
As far as the manufacturer's recommendations are concerned, I tend to believe that recommendation of 10W-30 instead of 5W-30 has more to do with the quality of earlier-API-grade 5W-30s than the oil shear. 10W-30 instead of 5W-30 was recommended very often by many manufacturers in the past. I believe, in the past, the viscosity-index improvers were of poor quality and they tended to not only shear too much but cause deposits as well. (They are plastics after all.) I think with modern ILSAC GF-4 and GF-5 or API SM or SN oils, such concerns are no longer major.
These days, the best reason to use a 10w-30 would be for a conventional HDEO. Conventional 5w-30s are definitely better now than they used to be.
Originally Posted By: Garak
Originally Posted By: Gokhan
As far as the manufacturer's recommendations are concerned, I tend to believe that recommendation of 10W-30 instead of 5W-30 has more to do with the quality of earlier-API-grade 5W-30s than the oil shear. 10W-30 instead of 5W-30 was recommended very often by many manufacturers in the past. I believe, in the past, the viscosity-index improvers were of poor quality and they tended to not only shear too much but cause deposits as well. (They are plastics after all.) I think with modern ILSAC GF-4 and GF-5 or API SM or SN oils, such concerns are no longer major.
These days, the best reason to use a 10w-30 would be for a conventional HDEO. Conventional 5w-30s are definitely better now than they used to be.
Agreed on a conventional SN/GF-5 5W-30 being adequate in virtually all applications recommending a conventional 10W-30. Although, you would see a better margin of protection and better performance (cleaning, oil life, etc.) with a quality synthetic.
However, regarding HDEO, API CJ-4 imposes a minimum HTHS limit of 3.5 cP. This high value is practically impossible to attain with a conventional 10W-30. For example, Shell Rotella T5 10W-30 CJ-4 is a synthetic blend.
Originally Posted By: Gokhan
As far as the manufacturer's recommendations are concerned, I tend to believe that recommendation of 10W-30 instead of 5W-30 has more to do with the quality of earlier-API-grade 5W-30s than the oil shear. 10W-30 instead of 5W-30 was recommended very often by many manufacturers in the past. I believe, in the past, the viscosity-index improvers were of poor quality and they tended to not only shear too much but cause deposits as well. (They are plastics after all.) I think with modern ILSAC GF-4 and GF-5 or API SM or SN oils, such concerns are no longer major.
These days, the best reason to use a 10w-30 would be for a conventional HDEO. Conventional 5w-30s are definitely better now than they used to be.
Agreed on a conventional SN/GF-5 5W-30 being adequate in virtually all applications recommending a conventional 10W-30. Although, you would see a better margin of protection and better performance (cleaning, oil life, etc.) with a quality synthetic.
However, regarding HDEO, API CJ-4 imposes a minimum HTHS limit of 3.5 cP. This high value is practically impossible to attain with a conventional 10W-30. For example, Shell Rotella T5 10W-30 CJ-4 is a synthetic blend.
Originally Posted By: Gokhan
However, regarding HDEO, API CJ-4 imposes a minimum HTHS limit of 3.5 cP. This high value is practically impossible to attain with a conventional 10W-30. For example, Shell Rotella T5 10W-30 CJ-4 is a synthetic blend.
I believe, but cannot be certain, that Mobil Delvac 1300 Super 10w-30 is a conventional. Shell still offers Rotella Triple Protection 10w-30. Both the Imperial Oil and SOPUS products are CJ-4, and neither gives any indication of being a synthetic blend. Oddly, the pour point of the Delvac 13w-30 is higher than that of the 15w-40. Neither the Delvac 1300 10w-30 nor the Rotella Triple Protection 10w-30 have particularly impressive pour points. Coupled with the language on the sheets, and assuming price point is on par with the corresponding 15w-40, I'd have to lean towards them being conventional. The SOPUS sheet even talks about high purity Group II base stocks.
As for 5w-30 in a 10w-30 legacy application, I'd stick with conventional unless there were mitigating circumstances. Something like a stock Chevy small block wouldn't care either way. It's certainly not hard on the oil.
However, regarding HDEO, API CJ-4 imposes a minimum HTHS limit of 3.5 cP. This high value is practically impossible to attain with a conventional 10W-30. For example, Shell Rotella T5 10W-30 CJ-4 is a synthetic blend.
I believe, but cannot be certain, that Mobil Delvac 1300 Super 10w-30 is a conventional. Shell still offers Rotella Triple Protection 10w-30. Both the Imperial Oil and SOPUS products are CJ-4, and neither gives any indication of being a synthetic blend. Oddly, the pour point of the Delvac 13w-30 is higher than that of the 15w-40. Neither the Delvac 1300 10w-30 nor the Rotella Triple Protection 10w-30 have particularly impressive pour points. Coupled with the language on the sheets, and assuming price point is on par with the corresponding 15w-40, I'd have to lean towards them being conventional. The SOPUS sheet even talks about high purity Group II base stocks.
As for 5w-30 in a 10w-30 legacy application, I'd stick with conventional unless there were mitigating circumstances. Something like a stock Chevy small block wouldn't care either way. It's certainly not hard on the oil.
Shell also makes Rotella T3 10W30...
I suspect at 12.1 cSt and using GII+ Basestock some RT3 and RTP 10W30 is not a blend but I also suspect they sometimes resort to adding GII to GIII to "make" GII+ Base stock which would technically be a blend by marketing definition.
I suspect at 12.1 cSt and using GII+ Basestock some RT3 and RTP 10W30 is not a blend but I also suspect they sometimes resort to adding GII to GIII to "make" GII+ Base stock which would technically be a blend by marketing definition.
I forgot about Mobil Delvac 1300 Super 10W-30. It has HTHS 3.6 cP and 100 C KV 11.9 cSt. It's a little bit of a cheat because the limit on 10W-30 is 12.4 cSt and 12.5 cSt would be considered 10W-40. I believe Mobil Delvac 1300 Super is strictly Group II+. So, it's almost a 10W-40 but not quite there as far as the oil flow and pressure are considered -- it misses it by 5%. So, you would benefit slightly less oil pressure (easier on the seals and oil pump) and better oil flow -- both dictated by KV -- without compromising much from the oil-film-thickness protection -- dictated by HTHS.
Since it's CJ-4 the NOACK would have to be less than 13%, another reason why it would have to be Group II+, in addition to the higher viscosity index.
Since it's CJ-4 the NOACK would have to be less than 13%, another reason why it would have to be Group II+, in addition to the higher viscosity index.
Gokhan -
You must know of Richard Feinman.
You must know of Richard Feinman.
Originally Posted By: mechtech2
Gokhan -
You must know of Richard Feinman.
Feynman was an interesting and unusual character and very intelligent.
Gokhan -
You must know of Richard Feinman.
Feynman was an interesting and unusual character and very intelligent.
Originally Posted By: Gene K
Shell also makes Rotella T3 10W30...
They have the two 10w-30 HDEOs up here, one marketed as conventional, one as semi-synthetic.
Originally Posted By: Gokhan
Since it's CJ-4 the NOACK would have to be less than 13%, another reason why it would have to be Group II+, in addition to the higher viscosity index.
I believe you are correct on that.
Shell also makes Rotella T3 10W30...
They have the two 10w-30 HDEOs up here, one marketed as conventional, one as semi-synthetic.
Originally Posted By: Gokhan
Since it's CJ-4 the NOACK would have to be less than 13%, another reason why it would have to be Group II+, in addition to the higher viscosity index.
I believe you are correct on that.
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