I have noticed after reading the specifications from several oil companies synthetic 5w30 & 10w30 the two oil weights are so close is there really any reason to have both? Do you think there is much advantage to the 10w30 synthetic offering anymore?
Synthetic 10/5-30?
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If I lived in the Keys or Miami/Dade, that's all I'd run.
IMO....In some cases Sheer stability.....for 10w.
Many older cars spec 10W-30 - including my 94 Pontiac Bonneville with a 3.8L V6. Most people buy whatever oil grade is printed on the fill cap - and most Quickie Lube places follow that guide as well. 10W-30 is likely more heat and burn off resistant for older cars since it has less VIIs.
A real (good) synthetic base will need (virtualy) no vii to achieve a 10w rating. Straight 30 is good for multiple reasons, without sacrificing cold flow performance down to the lowest temperature my region will ever see, so I see no reason to use any thing else.
Originally Posted By: Dyusik
A real (good) synthetic base will need (virtualy) no vii to achieve a 10w rating. Straight 30 is good for multiple reasons, without sacrificing cold flow performance down to the lowest temperature my region will ever see, so I see no reason to use any thing else.
If you are advocating straight weight oils v. multi-viscosity for modern automobiles, that is nuts.
A real (good) synthetic base will need (virtualy) no vii to achieve a 10w rating. Straight 30 is good for multiple reasons, without sacrificing cold flow performance down to the lowest temperature my region will ever see, so I see no reason to use any thing else.
If you are advocating straight weight oils v. multi-viscosity for modern automobiles, that is nuts.
Funny, I'm running 10w30 QSUD as Walmart was out of 5w30 in the 5qtjug.
Then I went home and looked at the SHELL PDS and I see the 10w30 has a -51C pour point ( vs -41C 5W30)
and a KV100 of: 10.3cSt (vs 10.8cSt 5W30 ).
The KV 40 was 61 cSt (vs 60cSt 5W30).
It runs fine in the spring with NO freezing temps anticipated.
Be curious to know if the HTHS is >=3.3cP to make it a "worthwhile" 10W; not just a 10W in name only.
Then I went home and looked at the SHELL PDS and I see the 10w30 has a -51C pour point ( vs -41C 5W30)
and a KV100 of: 10.3cSt (vs 10.8cSt 5W30 ).
The KV 40 was 61 cSt (vs 60cSt 5W30).
It runs fine in the spring with NO freezing temps anticipated.
Be curious to know if the HTHS is >=3.3cP to make it a "worthwhile" 10W; not just a 10W in name only.
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Originally Posted By: TomYoung
Originally Posted By: Dyusik
A real (good) synthetic base will need (virtualy) no vii to achieve a 10w rating. Straight 30 is good for multiple reasons, without sacrificing cold flow performance down to the lowest temperature my region will ever see, so I see no reason to use any thing else.
If you are advocating straight weight oils v. multi-viscosity for modern automobiles, that is nuts.
The requirement for a "straight weight" oil these days doesn't require that it meet a viscosity requirement when cold. These days with group II base oils they probably could qualify as multi-vis oils.
Originally Posted By: Dyusik
A real (good) synthetic base will need (virtualy) no vii to achieve a 10w rating. Straight 30 is good for multiple reasons, without sacrificing cold flow performance down to the lowest temperature my region will ever see, so I see no reason to use any thing else.
If you are advocating straight weight oils v. multi-viscosity for modern automobiles, that is nuts.
The requirement for a "straight weight" oil these days doesn't require that it meet a viscosity requirement when cold. These days with group II base oils they probably could qualify as multi-vis oils.
Originally Posted By: TomYoung
Originally Posted By: Dyusik
A real (good) synthetic base will need (virtualy) no vii to achieve a 10w rating. Straight 30 is good for multiple reasons, without sacrificing cold flow performance down to the lowest temperature my region will ever see, so I see no reason to use any thing else.
If you are advocating straight weight oils v. multi-viscosity for modern automobiles, that is nuts.
Pretty sure he was making the point that many synthetic straight 30w oils also meet the cold flow requirements to be a 10w30. Amsoil, for one, has a wide range of 10w30 products that are actually straight 30w base oils. No VII is needed. So it is not "nuts" to advocate a synthetic straight weight oil. Just depends on what is being discussed.
Originally Posted By: Dyusik
A real (good) synthetic base will need (virtualy) no vii to achieve a 10w rating. Straight 30 is good for multiple reasons, without sacrificing cold flow performance down to the lowest temperature my region will ever see, so I see no reason to use any thing else.
If you are advocating straight weight oils v. multi-viscosity for modern automobiles, that is nuts.
Pretty sure he was making the point that many synthetic straight 30w oils also meet the cold flow requirements to be a 10w30. Amsoil, for one, has a wide range of 10w30 products that are actually straight 30w base oils. No VII is needed. So it is not "nuts" to advocate a synthetic straight weight oil. Just depends on what is being discussed.
Originally Posted By: TiredTrucker
Pretty sure he was making the point that many synthetic straight 30w oils also meet the cold flow requirements to be a 10w30. Amsoil, for one, has a wide range of 10w30 products that are actually straight 30w base oils. No VII is needed. So it is not "nuts" to advocate a synthetic straight weight oil. Just depends on what is being discussed.
Well maybe but then they would have to be labeled as such (if they carry an API designation). They would be labeled as a multi-vis oil.
How many synthetic oils are there that are API straight weight? I'm not even sure how that could happen.
Pretty sure he was making the point that many synthetic straight 30w oils also meet the cold flow requirements to be a 10w30. Amsoil, for one, has a wide range of 10w30 products that are actually straight 30w base oils. No VII is needed. So it is not "nuts" to advocate a synthetic straight weight oil. Just depends on what is being discussed.
Well maybe but then they would have to be labeled as such (if they carry an API designation). They would be labeled as a multi-vis oil.
How many synthetic oils are there that are API straight weight? I'm not even sure how that could happen.
Originally Posted By: kschachn
Originally Posted By: TiredTrucker
Pretty sure he was making the point that many synthetic straight 30w oils also meet the cold flow requirements to be a 10w30. Amsoil, for one, has a wide range of 10w30 products that are actually straight 30w base oils. No VII is needed. So it is not "nuts" to advocate a synthetic straight weight oil. Just depends on what is being discussed.
Well maybe but then they would have to be labeled as such (if they carry an API designation). They would be labeled as a multi-vis oil.
How many synthetic oils are there that are API straight weight? I'm not even sure how that could happen.
There's really no real requirement for that. I thought that the requirement for a "single weight" oil is that it contain no VI improver. There's generally only minimum requirements. Almost any 0W-30 motor oil could legally be sold as a 10W-30 because it meets all the requirements.
Royal Purple has SAE 30/40/50 listed on the API EOLCS directory.
https://engineoil.api.org/Directory/EolcsResultsDetail?accountId=-1&companyId=10239&resultsUrl=%2FDirectory%2FEolcsResults%3FaccountId%3D-1%26companyName%3Droyal
Originally Posted By: TiredTrucker
Pretty sure he was making the point that many synthetic straight 30w oils also meet the cold flow requirements to be a 10w30. Amsoil, for one, has a wide range of 10w30 products that are actually straight 30w base oils. No VII is needed. So it is not "nuts" to advocate a synthetic straight weight oil. Just depends on what is being discussed.
Well maybe but then they would have to be labeled as such (if they carry an API designation). They would be labeled as a multi-vis oil.
How many synthetic oils are there that are API straight weight? I'm not even sure how that could happen.
There's really no real requirement for that. I thought that the requirement for a "single weight" oil is that it contain no VI improver. There's generally only minimum requirements. Almost any 0W-30 motor oil could legally be sold as a 10W-30 because it meets all the requirements.
Royal Purple has SAE 30/40/50 listed on the API EOLCS directory.
https://engineoil.api.org/Directory/EolcsResultsDetail?accountId=-1&companyId=10239&resultsUrl=%2FDirectory%2FEolcsResults%3FaccountId%3D-1%26companyName%3Droyal
Originally Posted By: y_p_w
There's really no real requirement for that. I thought that the requirement for a "single weight" oil is that it contain no VI improver. There's generally only minimum requirements. Almost any 0W-30 motor oil could legally be sold as a 10W-30 because it meets all the requirements.
Royal Purple has SAE 30/40/50 listed on the API EOLCS directory.
https://engineoil.api.org/Directory/EolcsResultsDetail?accountId=-1&companyId=10239&resultsUrl=%2FDirectory%2FEolcsResults%3FaccountId%3D-1%26companyName%3Droyal
I didn't know about the RP oils, that's interesting. I don't know how that is accomplished to be honest.
Actually the API does require that even for oils without VII but which are non-Newtonian. If an oil meets the requirements for a 0W-30 then it cannot be marketed as a 10W-30.
Per J300:
Quote:
Most oils will meet the viscosity requirements of at least one of the W grades. Nevertheless, consistent with historic practice, any Newtonian oil may be labeled as a single-grade oil (either with or without a W). Oils which are formulated with polymeric viscosity index improvers for the purpose of making them multiviscosity-grade products are non-Newtonian and must be labeled with the appropriate multiviscosity grade (both W and high-temperature grade). Since each W grade is defined on the basis of maximum cranking and pumping viscosities as well as minimum kinematic viscosities at 100 °C, it is possible for an oil to satisfy the requirements of more than one W grade. In labeling either a W grade or a multiviscosity grade oil, only the lowest W grade satisfied may be referred to on the label. Thus, an oil meeting the requirements for SAE grades 10W, 15W, 20W, 25W, and 30 must be referred to as an SAE 10W-30 grade only.
There's really no real requirement for that. I thought that the requirement for a "single weight" oil is that it contain no VI improver. There's generally only minimum requirements. Almost any 0W-30 motor oil could legally be sold as a 10W-30 because it meets all the requirements.
Royal Purple has SAE 30/40/50 listed on the API EOLCS directory.
https://engineoil.api.org/Directory/EolcsResultsDetail?accountId=-1&companyId=10239&resultsUrl=%2FDirectory%2FEolcsResults%3FaccountId%3D-1%26companyName%3Droyal
I didn't know about the RP oils, that's interesting. I don't know how that is accomplished to be honest.
Actually the API does require that even for oils without VII but which are non-Newtonian. If an oil meets the requirements for a 0W-30 then it cannot be marketed as a 10W-30.
Per J300:
Quote:
Most oils will meet the viscosity requirements of at least one of the W grades. Nevertheless, consistent with historic practice, any Newtonian oil may be labeled as a single-grade oil (either with or without a W). Oils which are formulated with polymeric viscosity index improvers for the purpose of making them multiviscosity-grade products are non-Newtonian and must be labeled with the appropriate multiviscosity grade (both W and high-temperature grade). Since each W grade is defined on the basis of maximum cranking and pumping viscosities as well as minimum kinematic viscosities at 100 °C, it is possible for an oil to satisfy the requirements of more than one W grade. In labeling either a W grade or a multiviscosity grade oil, only the lowest W grade satisfied may be referred to on the label. Thus, an oil meeting the requirements for SAE grades 10W, 15W, 20W, 25W, and 30 must be referred to as an SAE 10W-30 grade only.
Originally Posted By: kschachn
Originally Posted By: y_p_w
There's really no real requirement for that. I thought that the requirement for a "single weight" oil is that it contain no VI improver. There's generally only minimum requirements. Almost any 0W-30 motor oil could legally be sold as a 10W-30 because it meets all the requirements.
Royal Purple has SAE 30/40/50 listed on the API EOLCS directory.
https://engineoil.api.org/Directory/EolcsResultsDetail?accountId=-1&companyId=10239&resultsUrl=%2FDirectory%2FEolcsResults%3FaccountId%3D-1%26companyName%3Droyal
I didn't know about the RP oils, that's interesting. I don't know how that is accomplished to be honest.
Actually the API does require that even for oils without VII but which are non-Newtonian. If an oil meets the requirements for a 0W-30 then it cannot be marketed as a 10W-30.
Per J300:
Quote:
Most oils will meet the viscosity requirements of at least one of the W grades. Nevertheless, consistent with historic practice, any Newtonian oil may be labeled as a single-grade oil (either with or without a W). Oils which are formulated with polymeric viscosity index improvers for the purpose of making them multiviscosity-grade products are non-Newtonian and must be labeled with the appropriate multiviscosity grade (both W and high-temperature grade). Since each W grade is defined on the basis of maximum cranking and pumping viscosities as well as minimum kinematic viscosities at 100 °C, it is possible for an oil to satisfy the requirements of more than one W grade. In labeling either a W grade or a multiviscosity grade oil, only the lowest W grade satisfied may be referred to on the label. Thus, an oil meeting the requirements for SAE grades 10W, 15W, 20W, 25W, and 30 must be referred to as an SAE 10W-30 grade only.
It seems kind of strange, but their 50 seems to be fairly similar to their 20W-50 in terms of viscosities over warm temperatures and the VI.
http://www.royalpurpleconsumer.com/wp-content/uploads/PS_API_MotorOIl.pdf
However, the one thing that looks a bit different is that their straight weight oils are only certified to API SJ. I guess they could do things with it that they wouldn't be able to do with a multi-vis oil for the latest spec.
Originally Posted By: y_p_w
There's really no real requirement for that. I thought that the requirement for a "single weight" oil is that it contain no VI improver. There's generally only minimum requirements. Almost any 0W-30 motor oil could legally be sold as a 10W-30 because it meets all the requirements.
Royal Purple has SAE 30/40/50 listed on the API EOLCS directory.
https://engineoil.api.org/Directory/EolcsResultsDetail?accountId=-1&companyId=10239&resultsUrl=%2FDirectory%2FEolcsResults%3FaccountId%3D-1%26companyName%3Droyal
I didn't know about the RP oils, that's interesting. I don't know how that is accomplished to be honest.
Actually the API does require that even for oils without VII but which are non-Newtonian. If an oil meets the requirements for a 0W-30 then it cannot be marketed as a 10W-30.
Per J300:
Quote:
Most oils will meet the viscosity requirements of at least one of the W grades. Nevertheless, consistent with historic practice, any Newtonian oil may be labeled as a single-grade oil (either with or without a W). Oils which are formulated with polymeric viscosity index improvers for the purpose of making them multiviscosity-grade products are non-Newtonian and must be labeled with the appropriate multiviscosity grade (both W and high-temperature grade). Since each W grade is defined on the basis of maximum cranking and pumping viscosities as well as minimum kinematic viscosities at 100 °C, it is possible for an oil to satisfy the requirements of more than one W grade. In labeling either a W grade or a multiviscosity grade oil, only the lowest W grade satisfied may be referred to on the label. Thus, an oil meeting the requirements for SAE grades 10W, 15W, 20W, 25W, and 30 must be referred to as an SAE 10W-30 grade only.
It seems kind of strange, but their 50 seems to be fairly similar to their 20W-50 in terms of viscosities over warm temperatures and the VI.
http://www.royalpurpleconsumer.com/wp-content/uploads/PS_API_MotorOIl.pdf
However, the one thing that looks a bit different is that their straight weight oils are only certified to API SJ. I guess they could do things with it that they wouldn't be able to do with a multi-vis oil for the latest spec.
OP, This was link was posted in a recent thread, and it shows the Noack volatility figures for a group of Full Synthetic oils.
http://content.valvoline.com/pdf/valvoline_full_synthetic_with_maxlife_technology.pdf
It's for Valvoline Full Synthetic with MaxLife (2016)
noack % for ILSAC oil grades
0W20 = 11.4 %
5W20 = 9.3 %
5W30 = 10.2 %
10W30 = 6.3 %
You can see the big advantage of a 5W30 over a 10W30 when produced by the same company as companion products. The 10W30 is always less volatile and it contains less VII polymers to shear. So to me a 10W30 oil is cleaner, less volatile and more shear stable. They are all good things, but only if you live in a climate where it offers you acceptable cold starting ability.
A 10W oil should be good down to about 0F or -20C, any colder and I would switch to the 5W. But if like me, it never gets below freezing, then there is no real advantage to running a 5W oil. Mind you I'm running a 0W right now but only because I got it at a great sale price.
Anyway I personally don't think you should get any more cold starting than what you need. All other things being equal.
My one problem with 10W30 is that it is not a Dexos grade. To be honest my problem is with GM and Dexos who didn't allow the grade, not with the oil grade itself. I assume this was to make life simple for car owners, as 5W30 will cover most of customers adequately without any "confusing" look-up tables. I know 10W30 can make the quality cut, as I can get a great Castrol Edge 10W30 that is Euro A5/B5 rated, which I believe to be a higher standard than Dexos.
http://content.valvoline.com/pdf/valvoline_full_synthetic_with_maxlife_technology.pdf
It's for Valvoline Full Synthetic with MaxLife (2016)
noack % for ILSAC oil grades
0W20 = 11.4 %
5W20 = 9.3 %
5W30 = 10.2 %
10W30 = 6.3 %
You can see the big advantage of a 5W30 over a 10W30 when produced by the same company as companion products. The 10W30 is always less volatile and it contains less VII polymers to shear. So to me a 10W30 oil is cleaner, less volatile and more shear stable. They are all good things, but only if you live in a climate where it offers you acceptable cold starting ability.
A 10W oil should be good down to about 0F or -20C, any colder and I would switch to the 5W. But if like me, it never gets below freezing, then there is no real advantage to running a 5W oil. Mind you I'm running a 0W right now but only because I got it at a great sale price.
Anyway I personally don't think you should get any more cold starting than what you need. All other things being equal.
My one problem with 10W30 is that it is not a Dexos grade. To be honest my problem is with GM and Dexos who didn't allow the grade, not with the oil grade itself. I assume this was to make life simple for car owners, as 5W30 will cover most of customers adequately without any "confusing" look-up tables. I know 10W30 can make the quality cut, as I can get a great Castrol Edge 10W30 that is Euro A5/B5 rated, which I believe to be a higher standard than Dexos.
I would say that about a 15wXX, but 10wXX, by its very nature of meeting that spec, makes it good to -25c / -13F. And if one keeps their vehicle in a garage, like I do, when not using it, the 10w30 would be fine even colder than that. For all of the reasons mentioned before and this now, that is why my 2006 Cadillac CTS has gotten only a 10w30 for quite some time. Now that vehicle came along before dexos so all I concern myself with is the GM 6094M that the manual says my 3.6L engine needs. I figure the API SN RC and ILSAC GF-5 oil I use takes care of that. But I think you are probably right on all counts regarding why GM / dexos didn't include 10w30 in the mix.
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Think you are correct with the Dexos 5w30 - and these companies are in so deep with ILSAC & CAFE standards. 10w30 is my post warranty choice on GM. I have 3 spec'd for 5w30 and one 5w20. The last I had spec'd for 10w30 was a 2007 Chrysler 3.5L that my son still has - it runs real strong at 160k ... (M1 HM)
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