Do you think there is much difference between a synthetic 5w30 vs 10w30 or do you think that it is offered in both grades for guys like me who still run 10w30 synthetic in the summer thinking it is better to use it for summer driving/towing? In other words do the major oil companies just offer it for guys like me or is there really little difference in the two weights offered in synthetic?
5w30 vs 10w30 synthetic
- Thread starter Camprunner
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http://content.valvoline.com/pdf/valvoline_full_synthetic_with_maxlife_technology.pdf
5w30 NOACK: 10.2%
10w-30 NOACK: 6.3%
5w30 NOACK: 10.2%
10w-30 NOACK: 6.3%
And many of the 10W's aren't getting the R&D of the 5W's. In many cases the 5W's might be the better overall. Not much difference in the 2 though. I don't think you're typically going to find a 10w30 carrying top level mfg certs. And a number of those might still be carrying SL API rating.
Most people won't do the summer shift to 10W if they're doing 2 OCI's per year. They will just use the same oil all year round, often for a single OCI. Bitogers who buy 10w30 on sale have to find a use for it. And in New England, that's a decent summer oil, which can be mixed with 0/5W's if you're stashing oils.
Most people won't do the summer shift to 10W if they're doing 2 OCI's per year. They will just use the same oil all year round, often for a single OCI. Bitogers who buy 10w30 on sale have to find a use for it. And in New England, that's a decent summer oil, which can be mixed with 0/5W's if you're stashing oils.
69GTX +1
I think the 10w30 has the advantage in warmer temperatures because of less viscosity index improvers and the lower NOACK number (not as volatile).
First it depends on the oil in question. There are good 10w30's a bad 5w30's; and visa versa. Second it depends on the HTHS. If you are running a 30 anything, then this number is important. It describes the oils ability to withstand stress at op temp and that's what counts in the end
Originally Posted By: Camprunner
Do you think there is much difference between a synthetic 5w30 vs 10w30 or do you think that it is offered in both grades for guys like me who still run 10w30 synthetic in the summer thinking it is better to use it for summer driving/towing? In other words do the major oil companies just offer it for guys like me or is there really little difference in the two weights offered in synthetic?
My
is that the 10w30 is a bit more shear stable, and yes it could offer more protection in summer. This could be outdated thinking but I've seen no evidence against it. With my '04 Grand Cherokee (4.0) I ran 5w30, with the notable exception of towing a 6x12 trailer for 2200 miles in the middle of summer, with temps as high as 105°F(41°C). THAT oil change was 10w30 because I feel the same as you do.
Do you think there is much difference between a synthetic 5w30 vs 10w30 or do you think that it is offered in both grades for guys like me who still run 10w30 synthetic in the summer thinking it is better to use it for summer driving/towing? In other words do the major oil companies just offer it for guys like me or is there really little difference in the two weights offered in synthetic?
My
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Originally Posted By: Ramblejam
5w30 NOACK: 10.2%
10w-30 NOACK: 6.3%
Exactly, the 10W30 should have less VII's, lower Noack volatility, and be more shear stable than the equivalent 5W30 (all other things being equal).
With the winter (W) cold start rating, as much as you need, but not more than you need. If you need 0W or 5W, then get it. But if you don't need it, I prefer a 10W.
It's a shame Dexos1 doesn't allow a 10W30 grade, however 10W30 is still being developed and made to good specs, such as Euro A5/B5. The most recent full synthetic oil released by Castrol onto the Australian market was a 10W30.
Quote:
Australian Castrol Edge 10w30 (API SN, ACEA A5/B5, ILSAC GF-5)
Vis 40C = 66.2
Vis 100C = 10.47
Pour Point = -36C
TBN = 11.2
HTHS = 3.2
5w30 NOACK: 10.2%
10w-30 NOACK: 6.3%
Exactly, the 10W30 should have less VII's, lower Noack volatility, and be more shear stable than the equivalent 5W30 (all other things being equal).
With the winter (W) cold start rating, as much as you need, but not more than you need. If you need 0W or 5W, then get it. But if you don't need it, I prefer a 10W.
It's a shame Dexos1 doesn't allow a 10W30 grade, however 10W30 is still being developed and made to good specs, such as Euro A5/B5. The most recent full synthetic oil released by Castrol onto the Australian market was a 10W30.
Quote:
Australian Castrol Edge 10w30 (API SN, ACEA A5/B5, ILSAC GF-5)
Vis 40C = 66.2
Vis 100C = 10.47
Pour Point = -36C
TBN = 11.2
HTHS = 3.2
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And 10w30 has come into it's own major league with HDEO usage as well. All major HD engines are factory filled with 10w30 and have been for a while. And that is the recommendation by the OEM's.
If I did two OCI's every year I would do exactly that. 10w30 summer, 5w30 winter.
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Things made more sense when the OM had a page showing temperatures and oil grade choices. Furthermore - I have no interest in a car maker who tells me what brand to use either ...
Although I already have a stash of low NOACK Mobil 1 ESP 5w30 waiting in the garage for warmer temps (it's not quite the cold weather oil that plain Mobil 1 5W30 is), I'd sure think hard about buying (much cheaper) Mobil 1 10W30 for warm weather usage after the ESP is used up if I could find some recent info about it. I don't see any VOAs for the 10W30 in the past few years. Mobil typically is not really generous with the info on their websites, but it is interesting that the HTHS for the 10W30 is lower than the 5W30...
https://mobiloil.com/en/motor-oils/mobil-1/mobil-1
If I lived in Florida or Oz, I sure wouldn't think twice about using a 10WXX year round. You're likely to get a better NOACK compared to a 5WXX oil of the same brand and also extremely unlikely to ever notice any cold flow differences.
https://mobiloil.com/en/motor-oils/mobil-1/mobil-1
If I lived in Florida or Oz, I sure wouldn't think twice about using a 10WXX year round. You're likely to get a better NOACK compared to a 5WXX oil of the same brand and also extremely unlikely to ever notice any cold flow differences.
Originally Posted By: CT8
All things equal the 5W will be better choice at extreme low temperatures
I agree.
The thing is some BITOGers consider anything below freezing (32*F) to be extreme....while others consider 0*F not to be 'extreme low'. I would think a synthetic 10w30 would work well down to about 15* to 20*F....below that I'd want the 5w30.
All things equal the 5W will be better choice at extreme low temperatures
I agree.
The thing is some BITOGers consider anything below freezing (32*F) to be extreme....while others consider 0*F not to be 'extreme low'. I would think a synthetic 10w30 would work well down to about 15* to 20*F....below that I'd want the 5w30.
I used conventional 10w30 in everything for decades. It will crank and start fine well below zero, although vehicles complain a bit at those temps. For temps above freezing there is no discernible advantage to a 5w30 that I can tell. And just about anything will purr along like a kitten on 10w30 regardless of it's spec, it's just about a universal oil in my experience.
I still do not hesitate to run it if winter temps will not be encountered during the OCI. That said, today's 5w30's are really good and generally what I run in our 20 grade spec'd vehicles.
I still do not hesitate to run it if winter temps will not be encountered during the OCI. That said, today's 5w30's are really good and generally what I run in our 20 grade spec'd vehicles.
I guess primarily living in the northern tier of the country, 10w30 even into sub zero F temps not a real concern. Growing up, my dad wouldn't use anything but a 30w year round. Never lost an engine. My comfort zone wouldn't let me do that, but I have no problem with 10w30 year round. Even at -16F we had a couple days ago.
Originally Posted By: Virtus_Probi
Although Mobil typically is not really generous with the info on their websites, but it is interesting that the HTHS for the 10W30 is lower than the 5W30...
If you want a bit more HTHS, have you considered Mobil 1 10W30 HM, with HTHS = 3.5 cP
Mobil 1 5W30 HM = 3.3 HTHS
Regular Mobil 1 5W30 = 3.1 HTHS
Regular Mobil 1 10W30 = 3.0 HTHS.
The Mobil 1 High Mileage oils, are performance oils in disguise.
Although Mobil typically is not really generous with the info on their websites, but it is interesting that the HTHS for the 10W30 is lower than the 5W30...
If you want a bit more HTHS, have you considered Mobil 1 10W30 HM, with HTHS = 3.5 cP
Mobil 1 5W30 HM = 3.3 HTHS
Regular Mobil 1 5W30 = 3.1 HTHS
Regular Mobil 1 10W30 = 3.0 HTHS.
The Mobil 1 High Mileage oils, are performance oils in disguise.
Originally Posted By: KCJeep
That said, today's 5w30's are really good and generally what I run in our 20 grade spec'd vehicles.
I like your style KCJeep
That said, today's 5w30's are really good and generally what I run in our 20 grade spec'd vehicles.
I like your style KCJeep
Originally Posted By: SR5
Originally Posted By: Virtus_Probi
Although Mobil typically is not really generous with the info on their websites, but it is interesting that the HTHS for the 10W30 is lower than the 5W30...
If you want a bit more HTHS, have you considered Mobil 1 10W30 HM, with HTHS = 3.5 cP
Mobil 1 5W30 HM = 3.3 HTHS
Regular Mobil 1 5W30 = 3.1 HTHS
Regular Mobil 1 10W30 = 3.0 HTHS.
The Mobil 1 High Mileage oils, are performance oils in disguise.
Mobil 1 10w40 HM in particular.
Originally Posted By: Virtus_Probi
Although Mobil typically is not really generous with the info on their websites, but it is interesting that the HTHS for the 10W30 is lower than the 5W30...
If you want a bit more HTHS, have you considered Mobil 1 10W30 HM, with HTHS = 3.5 cP
Mobil 1 5W30 HM = 3.3 HTHS
Regular Mobil 1 5W30 = 3.1 HTHS
Regular Mobil 1 10W30 = 3.0 HTHS.
The Mobil 1 High Mileage oils, are performance oils in disguise.
Mobil 1 10w40 HM in particular.
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