Why no 10w30
- Thread starter Camprunner
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There is a plethora of people out there that are not affiliated with BITOG that still use 10W30 without blinking an eye.
i use 10-30 almost everywhere. many car owners don't even read the owners manual let alone know a 10-30 is a better choice UNLESS your in a colder climate + need a little better cold flow. using at least a group III "full fake synthetic" that has better cold flow than lesser blends is best for most but its NEVER a one size fits all!!! also worn engines or extreme heat a 15-40 is a better choice IMO!!
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It's funny that you ask why not 10W30 with today's more demanding engines.
How long was it the go to grade for? I know that in the fifties and sixties the oil aisle in stores probably looked like something from Australia today.
It was a almost universal grade, then all of the sudden they went to light oils. Then all of the sudden they started producing engines that would shear oil like they cut hair in the military!
It would seem that they just cut OCIs to help the shearing, as that what? 1%-2% is so important to CAFE.
In the business of selling cars is probably the correct answer.
How long was it the go to grade for? I know that in the fifties and sixties the oil aisle in stores probably looked like something from Australia today.
It was a almost universal grade, then all of the sudden they went to light oils. Then all of the sudden they started producing engines that would shear oil like they cut hair in the military!
It would seem that they just cut OCIs to help the shearing, as that what? 1%-2% is so important to CAFE.
In the business of selling cars is probably the correct answer.
Originally Posted By: SilverFusion2010
Originally Posted By: mx5miata
newer engines with tighter tolerances and fuel economy also easy flow at cold temp starts. I am pretty sure Chevy and Ford turbocharged cars use 5w30
Your statement about tolerances is wrong. This has been parroted on the internet for ages and it is wrong. Engines can operate on a broad range of grades. The engine that calls for 0w-20 in America is often run with 5w-30 or 10w-40 in Europe.
In fact, engines that run straight mineral 50 viscosity oil (piston aircraft engines) use some of the exact same bearing clearances as modern car engines.
Originally Posted By: mx5miata
newer engines with tighter tolerances and fuel economy also easy flow at cold temp starts. I am pretty sure Chevy and Ford turbocharged cars use 5w30
Your statement about tolerances is wrong. This has been parroted on the internet for ages and it is wrong. Engines can operate on a broad range of grades. The engine that calls for 0w-20 in America is often run with 5w-30 or 10w-40 in Europe.
In fact, engines that run straight mineral 50 viscosity oil (piston aircraft engines) use some of the exact same bearing clearances as modern car engines.
Patman
Staff member
I've been saying this on here for years now but 10w30 is obsolete, at least in terms of synthetics, because a 5w30 can do everything the 10w30 can do, with the added benefit of better flow on cold starts.
10w30 factory fill in Honda NSX and S2000.
Originally Posted By: john_pifer
Originally Posted By: Camprunner
Why don't car manufacturers recommend 10w30 today especially with all the turbo models sold now I would think it would hold up better under hard use?
The only reason is the marginal increase in economy with a 5W, and marketing by the oil companies.
You're correct; 10W will hold up better in an engine that's hard on oil, such as my 2016 WRX (turbo, GDI, boxer, high power density). Which is why I run PPPP 10W-30 year-round, when it calls for a 5W.
10Ws will also have much lower NOACK. PPPP is the best you'll find outside of an expensive boutique oil, at 4.7%. Matter of fact, I actually don't know of a boutique oil with better NOACK values. Maybe some kind of straight-grade might beat it.
Lively NOACK discussion going on Here currently.
PPPP? What oil does the FOUR Ps represent?
Originally Posted By: Camprunner
Why don't car manufacturers recommend 10w30 today especially with all the turbo models sold now I would think it would hold up better under hard use?
The only reason is the marginal increase in economy with a 5W, and marketing by the oil companies.
You're correct; 10W will hold up better in an engine that's hard on oil, such as my 2016 WRX (turbo, GDI, boxer, high power density). Which is why I run PPPP 10W-30 year-round, when it calls for a 5W.
10Ws will also have much lower NOACK. PPPP is the best you'll find outside of an expensive boutique oil, at 4.7%. Matter of fact, I actually don't know of a boutique oil with better NOACK values. Maybe some kind of straight-grade might beat it.
Lively NOACK discussion going on Here currently.
PPPP? What oil does the FOUR Ps represent?
Originally Posted By: Camprunner
Why don't car manufacturers recommend 10w30 today especially with all the turbo models sold now I would think it would hold up better under hard use?
Because when subjected to certain legislation, automakers can only legally recommend the exact same grade of oil used to officially qualify for EPA ratings-and that grade would be the 20's and 16's in the realm of light passenger vehicles. When you see a 30 still recommended on a brand new passenger vehicle, you can be sure it's for a demanding application where 20s and 16s will not adequately perform, and that the W number will be as low as practicable, again for regulatory qualification. That leaves 10W30 as a grade the odd guy out by process of elimination in the quest for highest statistical FE in light passenger vehicles.
10W30 might be 'down' in modern passenger vehicles, but it's certainly not out. The fact that it's not the grade used to qualify for regulatory standards (and thus not recommended) has nothing to do with flow, protection, tighter clearances, microfinishes, or being 'old spec' (tip: it's as old as the others).
Fact is 10W30 grade is making a big resurgence in the eco diesel market. FA-4 diesel oils are the "Eco oil" for modern diesels and are becoming recommended more and more. Fun fact about FA-4 10W30's, they're viscometrically very similar to much ILSAC 10W30s. Then beyond that, there are the higher HTHS HD 10W30s mainstays that have been servicing API C-standards for decades.
Don't worry, there will be 10W30s around for a long while yet.
Why don't car manufacturers recommend 10w30 today especially with all the turbo models sold now I would think it would hold up better under hard use?
Because when subjected to certain legislation, automakers can only legally recommend the exact same grade of oil used to officially qualify for EPA ratings-and that grade would be the 20's and 16's in the realm of light passenger vehicles. When you see a 30 still recommended on a brand new passenger vehicle, you can be sure it's for a demanding application where 20s and 16s will not adequately perform, and that the W number will be as low as practicable, again for regulatory qualification. That leaves 10W30 as a grade the odd guy out by process of elimination in the quest for highest statistical FE in light passenger vehicles.
10W30 might be 'down' in modern passenger vehicles, but it's certainly not out. The fact that it's not the grade used to qualify for regulatory standards (and thus not recommended) has nothing to do with flow, protection, tighter clearances, microfinishes, or being 'old spec' (tip: it's as old as the others).
Fact is 10W30 grade is making a big resurgence in the eco diesel market. FA-4 diesel oils are the "Eco oil" for modern diesels and are becoming recommended more and more. Fun fact about FA-4 10W30's, they're viscometrically very similar to much ILSAC 10W30s. Then beyond that, there are the higher HTHS HD 10W30s mainstays that have been servicing API C-standards for decades.
Don't worry, there will be 10W30s around for a long while yet.
Originally Posted By: ammolab
PPPP? What oil does the FOUR Ps represent?
>Pretty Platinumized Pure Protection
>Pennzoil Platinum Palladium Pewter
PPPP? What oil does the FOUR Ps represent?
>Pretty Platinumized Pure Protection
>Pennzoil Platinum Palladium Pewter
4WD
$50 site donor 2024
Originally Posted By: PeterPolyol
Originally Posted By: ammolab
PPPP? What oil does the FOUR Ps represent?
>Pretty Platinumized Pure Protection
>Pennzoil Platinum Palladium Pewter
Perfectly Paraphrased Peter Polyol.
Originally Posted By: ammolab
PPPP? What oil does the FOUR Ps represent?
>Pretty Platinumized Pure Protection
>Pennzoil Platinum Palladium Pewter
Perfectly Paraphrased Peter Polyol.
Originally Posted By: ammolab
Originally Posted By: john_pifer
Originally Posted By: Camprunner
Why don't car manufacturers recommend 10w30 today especially with all the turbo models sold now I would think it would hold up better under hard use?
The only reason is the marginal increase in economy with a 5W, and marketing by the oil companies.
You're correct; 10W will hold up better in an engine that's hard on oil, such as my 2016 WRX (turbo, GDI, boxer, high power density). Which is why I run PPPP 10W-30 year-round, when it calls for a 5W.
10Ws will also have much lower NOACK. PPPP is the best you'll find outside of an expensive boutique oil, at 4.7%. Matter of fact, I actually don't know of a boutique oil with better NOACK values. Maybe some kind of straight-grade might beat it.
Lively NOACK discussion going on Here currently.
PPPP? What oil does the FOUR Ps represent?
PENNZOIL PLATINUM PURE PLUS
Originally Posted By: john_pifer
Originally Posted By: Camprunner
Why don't car manufacturers recommend 10w30 today especially with all the turbo models sold now I would think it would hold up better under hard use?
The only reason is the marginal increase in economy with a 5W, and marketing by the oil companies.
You're correct; 10W will hold up better in an engine that's hard on oil, such as my 2016 WRX (turbo, GDI, boxer, high power density). Which is why I run PPPP 10W-30 year-round, when it calls for a 5W.
10Ws will also have much lower NOACK. PPPP is the best you'll find outside of an expensive boutique oil, at 4.7%. Matter of fact, I actually don't know of a boutique oil with better NOACK values. Maybe some kind of straight-grade might beat it.
Lively NOACK discussion going on Here currently.
PPPP? What oil does the FOUR Ps represent?
PENNZOIL PLATINUM PURE PLUS
Originally Posted By: hatt
Manufacturers are in the business of selling cars.
Well then they are failing. People own cars longer than at any point in history.
Manufacturers are in the business of selling cars.
Well then they are failing. People own cars longer than at any point in history.
Originally Posted By: dave1251
Originally Posted By: hatt
Manufacturers are in the business of selling cars.
Well then they are failing. People own cars longer than at any point in history.
Yes but the worldwide market is growing. Places that had few cars 10-20 years ago are the hot markets.
Originally Posted By: hatt
Manufacturers are in the business of selling cars.
Well then they are failing. People own cars longer than at any point in history.
Yes but the worldwide market is growing. Places that had few cars 10-20 years ago are the hot markets.
Originally Posted By: Patman
I've been saying this on here for years now but 10w30 is obsolete, at least in terms of synthetics, because a 5w30 can do everything the 10w30 can do, with the added benefit of better flow on cold starts.
Yeah, but you come from Canada, and I come from Australia. I think local climate should be taken into account.
In almost all of Australia you can run 20W50 year round, with a few exceptional places using 15W40 as a winter grade.
To me 5W30 and 10W30 are practically identical in cold starting performance. But given the same base stock, same add pack, same VII chemistry, then the 10W30 will always give me lower Noack volatility and better shear stability compared to the equivalently formulated 5W30.
To me going to a 5W30 would be giving away stuff I want for stuff I don't need. A poor bargain in my climate, but a good bargain in your climate.
I've been saying this on here for years now but 10w30 is obsolete, at least in terms of synthetics, because a 5w30 can do everything the 10w30 can do, with the added benefit of better flow on cold starts.
Yeah, but you come from Canada, and I come from Australia. I think local climate should be taken into account.
In almost all of Australia you can run 20W50 year round, with a few exceptional places using 15W40 as a winter grade.
To me 5W30 and 10W30 are practically identical in cold starting performance. But given the same base stock, same add pack, same VII chemistry, then the 10W30 will always give me lower Noack volatility and better shear stability compared to the equivalently formulated 5W30.
To me going to a 5W30 would be giving away stuff I want for stuff I don't need. A poor bargain in my climate, but a good bargain in your climate.
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I tested the theory and proved the tolerance between internal engine components and your engine oil selection is true. Tighter the tolerance, thinner the oil. Test vehicle was a 2013 Dodge Ram RCSB 5.7, manufacturer recommended 5w20 switched to 5w30 weight oil. While canyon racing in north Georgia mountains my oil sump temperatures were 12-16 degrees hotter than the 5w20 running the thicker 5w30. Why? Because internal engine components are cooled by oil directly and cooled by coolant indirectly. Thinner oils flow better than thick oil's pulling more heat from Internal engine components and lubricate more effectively. Thicker oil's flow slower through internal engine components pulling less heat from the engine, Drive up bearing temperatures and the oil meets or exceeds it thermal break down point. Oil in these areas of the engine can be 90 degrees hotter than the oil sump temperatures. As we all know oil is application specific, and the clearances between internal engine components is something that should be considered when making your oil selection.
Originally Posted By: Patman
I've been saying this on here for years now but 10w30 is obsolete, at least in terms of synthetics, because a 5w30 can do everything the 10w30 can do, with the added benefit of better flow on cold starts.
What about for conventional? When I asked around, people thought it a bad idea for me to run extended OCI's on my 5S-FE, due to its reputation as a sludger. I've proven that it does have a fair amount of varnish. But running synthetic for just 5k seems... wrong... in an economy motor. So I just run conventional 5W30. Which I doubt is being taxed in any way.
I've been saying this on here for years now but 10w30 is obsolete, at least in terms of synthetics, because a 5w30 can do everything the 10w30 can do, with the added benefit of better flow on cold starts.
What about for conventional? When I asked around, people thought it a bad idea for me to run extended OCI's on my 5S-FE, due to its reputation as a sludger. I've proven that it does have a fair amount of varnish. But running synthetic for just 5k seems... wrong... in an economy motor. So I just run conventional 5W30. Which I doubt is being taxed in any way.
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