Thick vs thin debate...

I'm starting to become of the opinion that the "harm" a lot of folks see out of thinner oils is not due to the viscosity but the presence of Vi improvers. I run 5w-20 in the winter and 10w-30 in the summer now in both vehicles, Corolla and Impreza. I'm not going to run 15w-40 unless either starts to drink oil. I just like an oil with less VII as that is shown to contribute to timing chain wear sometimes.
 
Can you tell me some 5W-30 oil that is HTHS 3.5? I'd much appreciate it if you will. Thank you.
Sure!
Please review Chevron DELO® 400 XSP SAE 5W-30 and Shell ROTELLA® T6 Multi-Vehicle 5W-30.
Both are SN-rated.
 
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What I've learned from people who've actually been involved in actually formulating and engineering lubricants (Shannow,Doug,etc) is that viscosity is what keeps the parts separated and the additives kick in when the oil film is breached. If thinner protects better, why doesn't only 0W2 (the thinnest I've personally seen) oil exist, and then why stop there? I guess the thinnest we could possibly go would be 0W0? I'm guessing 0W is the lowest baseline, and that there are no -0's possible?
 
What I've learned from people who've actually been involved in actually formulating and engineering lubricants (Shannow,Doug,etc) is that viscosity is what keeps the parts separated and the additives kick in when the oil film is breached. If thinner protects better, why doesn't only 0W2 (the thinnest I've personally seen) oil exist, and then why stop there? I guess the thinnest we could possibly go would be 0W0? I'm guessing 0W is the lowest baseline, and that there are no -0's possible?
True ... everyone needs to read this article. Viscosity is the key, AW/AF additives pick up where viscosity fails.

 
It seems that the bigoted opinions on thinner oils will persist. The myriad of SAE papers, historical data, and independent testing just cannot change the biased thinking of otherwise intelligent people.
But on the other hand, SAE papers and data shows that viscosity is still the main factor in keeping moving parts separated. That's always been the case, and always will be the case because it's the main backbone of tribology.
 
What I've learned from people who've actually been involved in actually formulating and engineering lubricants (Shannow,Doug,etc) is that viscosity is what keeps the parts separated and the additives kick in when the oil film is breached. If thinner protects better, why doesn't only 0W2 (the thinnest I've personally seen) oil exist, and then why stop there? I guess the thinnest we could possibly go would be 0W0? I'm guessing 0W is the lowest baseline, and that there are no -0's possible?


Where can one find this 0w2 oil?
 
I think lots of people with "bigoted opinions" like more MOFT because they don't drive like grandma ... so any thin oil would work for going to grocery store.
 
I think lots of people with "bigoted opinions" like more MOFT because they don't drive like grandma ... so any thin oil would work for going to grocery store.


Not exactly. Unless you are towing big loads over mountain passes or racing etc etc, the modern engine cruises along at a leisurely rpm.
 

I studied oil viscosity while in high school. In the 1970s there was a lack of shear stability due to lesser base oils, fuel dilution and inferior additives. Big, powerful engines ended up running on 10? and 20 grade motor oils. So thin oils in SI engines is nothing new.

For decades now millions of cars, trucks and big SUVs have been running on 20 grade oils without ill effects. These thinner oils result in better fuel economy, more power and improved get up and go especially when we are driving shorter distances with each turn of the key. And thinner oils are on the way.

It seems that the bigoted opinions on thinner oils will persist. The myriad of SAE papers, historical data, and independent testing just cannot change the biased thinking of otherwise intelligent people.

FYI: The owner of Ferrari of Tampa Bay just bought my Enzo after exhaustive testing in the shop. The engine was as good as new according to the mechanics analysis, actually better than any Enzo motor they have ever seen or cared for. Incidentally, I have run nothing but 0-20 and 0-30 grade oils in the engine that is spec'ed for a 10W-60 oil. Studies will continue in the 812 Superfast. It is spec'ed for a 5-40 and has 150 more HP than the Enzo.

AEHaas

just curious, are you are allowing your high school oil viscosity studies override the manufacturer's 10W60 spec?
Do you know more than the designers? That doesn't sound like a very smart idea!
 
"Do you know more than the designers?"

No. However I have been in direct contact and have had technical discussions with Ferraris technical staff. They have told me they are recommending thinner oils for general driving around town now and only thicker oils for racing conditions. There is a lot more to know here that I cannot be bothered to write up. Call me if you need more information.

And I may very well have used 10W-60 oil if I was to race the Enzo on the track for a few hours at 225 MPH. The engine oil temperature at a steady 70 MPH was around 185F. This was with a 30 grade oil.
As far as the 812 Superfast there is no way you can drive around town and use the available 800 HP so as to heat up the oil. As they spec a 40 grade oil certainly a 20 grade would be more than enough away from the track. Right now with the 40 grade oil and the engine fully warmed up the pressure is still over 30 PSI at 650 RPM idle. At 9,000 RPM the pressure is "pop off" limited to 80-90 PSI.

AEHaas
 
But on the other hand, SAE papers and data shows that viscosity is still the main factor in keeping moving parts separated. ...
Even "the main factor" in minimizing wear of parts that don't enjoy full hydrodynamic separation, like rocker arms, for example?

Bearings are relatively easy to think about and analyze with standard formulae, but normally outlast other wear-prone parts.
 
Even "the main factor" in minimizing wear of parts that don't enjoy full hydrodynamic separation, like rocker arms, for example?

Bearings are relatively easy to think about and analyze with standard formulae, but normally outlast other wear-prone parts.
Any time there is relative movement between parts then the viscosity plays a roll in MOFT and parts separation ... even if not in the full hydrodynamic realm of lubrication.
 
The engine in my vehicle is the only gas engine Ford recommended 5W30 in instead of 5W20 for about a decade. That scares me and I can't bring myself to put anything lighter than 5W30 in it.
As a thickie,I could never go thinner than spec. W30s seem like the perfect balance between thin enough and thick enough.
 
"Do you know more than the designers?"

No. However I have been in direct contact and have had technical discussions with Ferraris technical staff. They have told me they are recommending thinner oils for general driving around town now and only thicker oils for racing conditions. There is a lot more to know here that I cannot be bothered to write up. Call me if you need more information.

And I may very well have used 10W-60 oil if I was to race the Enzo on the track for a few hours at 225 MPH. The engine oil temperature at a steady 70 MPH was around 185F. This was with a 30 grade oil.
As far as the 812 Superfast there is no way you can drive around town and use the available 800 HP so as to heat up the oil. As they spec a 40 grade oil certainly a 20 grade would be more than enough away from the track. Right now with the 40 grade oil and the engine fully warmed up the pressure is still over 30 PSI at 650 RPM idle. At 9,000 RPM the pressure is "pop off" limited to 80-90 PSI.

AEHaas
Aren’t you on another thread talking about how your Ferrari is using two quarts of oil in 500 miles and is in danger of going down to zero in the sump?

I would really, and quite honestly, seriously question any technical discussions you’ve had with Ferrari’s technical staff. As far as I know, Ferrari isn’t generally forthcoming with information, so I wonder who exactly is supplying you with technical information. If it’s a technician or ANYONE AT A FERRARI DEALER, I would not trust or listen to their technical information if they’re telling you to run 0W20 in a 12 cylinder 2.5 million dollar race car. In fact, if it is the dealer telling you to do this, call Ferrari directly and let them know. They will probably give you a new Ferrari and strip that dealer of its license.
 
I am talking with Ferrari of North America (FNA) in NJ.

Not to worry about running out of oil. The sump is dry, actually no room at all for oil down there. A separate tank of oil holds essentially all the oil, about 14 quarts.

AEHaas
 

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I am talking with Ferrari of North America (FNA) in NJ.

Not to worry about running out of oil. The sump is dry, actually no room at all for oil down there. A separate tank of oil holds essentially all the oil, about 14 quarts.

AEHaas
IIRC … you have experimented with various viscosity oils in Ferrari engines for the best part of a decade ?
 
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