0W-16 Strength & Durability

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This is interesting. I understand how running the oil at lower temps can be beneficial due in part to its thicker viscosity. Over the year or so that I've been here, that concept has been brought up with the idea that running an engine colder, such as when doing short trips, actually affords better protection.

So, with oil running cooler for better protection, might it also be true that cooler oil temps prevent the oil from getting hot enough to burn off water, gasses, and other contaminants which, in turn, degrades the effectiveness of the oil and reduces its long-term viability and making 10,000-mile OCIs problematical? Any thoughts on this, any experience with the issue ... or is it even a consideration?
Yes, it's a double-edges sword. You also need oil temperatures to be hot enough to vaporize water condensation and fuel dilution from piston ring blow-by. The ideal operating tempeature IMO would be 200-220F. Engines are also more fuel efficient if they run a bit hotter than not.
 
In the dino years. I am SP oils now.
In the dino years? Viscosity is viscosity, regardless of the API rating (... Sx, SN, SP or whatever). Granted, the HTHS viscosity can change slightly due to the oil VII formulation, and we all know that it's the HTHS viscosity that is really the way to look at the protection level due to viscosity. The relationship between viscosity and MOFT will never be dependent on the API rating if that's what you're referring to.
 
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IMO You start your engine. The oil is way too thick at 0w. Then while driving and the temperature warm up to operating temperature. The base oil synthetic gives you some viscosity index but the rest need some VII. In reality wear happens when you first start your engine. The more RPM the engine gets the safer when at operating temperature as far as MOFT.
Way too thick at 0W? Not really. If 0W was "too thick" for a cold start-up, then over half the cars on the road wouldn't make it to 100K miles using 5W, 20W, 15W and 20W.

Wear happens at cold start mostly when the oil is too thick for a cold start in the ambient conditions that it's used in. The use of the "W" rating is suppose to help people use the correct viscosity for their cold-startup conditions. Also, obviously some parts will have some rubbing contact for the first few RPM of the engine until oil can get fully supplied to some areas, especially if the ADBV in the filter let some oil drain out of the galleries and/or if the engine has sat a very long time vs not. Sure, there will always be a thin oil film on parts after shut-down, but that super small film may not give full parts separation protection on a cold start a week later.
 
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Really 40 c is over 100 f and the viscosity index improvers are not designed for the most critical part of oil protection, the engine cold start. It really does not matter how low the oil can go and still crank.
Parts separation, which is what prevents engine wear, is operating mainly on the oil viscosity. Once the engine fires up and there is adequate oil on all the moving parts then I don't think there is really any more wear during the warm-up stage.

What's wearing out the parts if the engine is running with the oil at 40C if the parts are being separated better with more MOFT than if the oil was at 100C ?
 
Parts separation, which is what prevents engine wear, is operating mainly on the oil viscosity. Once the engine fires up and there is adequate oil on all the moving parts then I don't think there is really any more wear during the warm-up stage.

What's wearing out the parts if the engine is running with the oil at 40C if the parts are being separated better with more MOFT than if the oil was at 100C ?
Ford and Honda did factory fills of 5w20 in 2002. My 2008 Miata called for 5w-20. Imagine fear has driven some to 20 years of the OEM calling out sub standard viscosity and others claiming the engine was designed for it. Personally IMO 20 years have proven 20 weight oils work.
 
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Ford and Honda did factory fills of 5w20 in 2002. My 2008 Miata called for 5w-20. Imagine fear has driven some to 20 years of the OEM calling for sub standard viscosity and others claiming the engine was designed for it.
Engines were never "designed" for xW-20. Just the fact that the same exact engine used in other countries that the OM calls out a whole spectrum of oil viscosity by the manufacturer. The car makers just discovered that engines will still make it to pretty high mileage using xW-20 and tried to reap the benefits in order to try and meet the ever increasing CAFE target.

Now engines that spec 0W-16 and 0W-8 may very well have design features that help them use that thin of a viscosity better than an engine not designed for that thin of oil (ie, journal bearing design, etc). Still, those engines could use a thicker viscosity way easier than the other way around. That's why the API uses a different bottle "shield/logo" for 0W-16, so someone doesn't use 0W-16 in a vehicle that specs xW-20 or higher.
 
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Ford and Honda did factory fills of 5w20 in 2002. My 2008 Miata called for 5w-20. Imagine fear has driven some to 20 years of the OEM calling out sub standard viscosity and others claiming the engine was designed for it. Personally IMO 20 years have proven 20 weight oils work.
They work adequately under most circumstances but that isn’t the question nor the topic at hand. Of course blaming the opposition on “fear” is deflection, but I digress.
 
They work adequately under most circumstances but that isn’t the question nor the topic at hand. Of course blaming the opposition on “fear” is deflection, but I digress.
Well when the assumption is the engine was designed for higher viscosity but slaps a lower weight due to CAFE does not fly to me. The engine engineering and oil viscosity is a package. If oil is the blood of the engine what do you call thick blood?
 
This STILL is not the 2001 Honda Civic US oil chart that just has an arrow that says 5W-20 across the whole thing, from like -10 to 120°F.

Maybe they thought it will never see above 120. So, in places like Vegas and Florida, where it can hit that every day for a month or two..now I'm thinking.
Where in Florida did you read it gets 120f?? And for a month?
 
Well when the assumption is the engine was designed for higher viscosity but slaps a lower weight due to CAFE does not fly to me. The engine engineering and oil viscosity is a package. If oil is the blood of the engine what do you call thick blood?
Engines are designed to run a large spectrum of oil viscosity ... that's the point people are missing. If that wasn't true, the same engines in other non-CAFE driven countries wouldn't specify the whole range of viscosity in the OM.

In the case of vehicles that spec 8 and 16, then there are some specific design aspects, but not really for vehicles specing 20+ oils. Already mentioned why. It just so happens the push to use lower and lower viscosity is driven by CAFE. Like I mentioned earlier in this thread, what if CAFE didn't even exist. Do you really think engineers would be specifying 16 and 20 oils and operate the engine on the edge of adequate MOFT? I don't from an engineering viewpoint ... why would they when a little more viscosity headroom gives better protection.
 
Engines are designed to run a large spectrum of oil viscosity ... that's the point people are missing. It just so happens the push to use lower and lower viscosity is driven by CAFE. Like I mentioned earlier in this thread, what if CAFE didn't even exist. Do you really think engineers would be specifying 16 and 20 oils? I don't.
I do. Selling "better fuel economy" would still be important to many drivers. I guess it depends on how much more the development and manufacturering of these oils would be in comparison to 10w30 and 40s.
 
I do. Selling "better fuel economy" would still be important to many drivers. I guess it depends on how much more the development and manufacturer of these oils would be in comparison to the 10w30 and 40s.
Fuel economy is a lot more important to the vehicle manufacture for hitting the CAFE targets. I highly doubt anyone is really that concerned about the 0.05 MPG difference their vehicle might get if using thin vs thick oil. One large throttle opening to spin the engine up high in RPM during stop and go driving on that tank of gas would smoke any gains seen in using a thinner oil over the length of that tank of gas. Maybe if someone drove on the freeway 95+% of the time (with no traffic) on cruise control where the speed never change, it might be something actually seen when they filled up.
 
Engines are designed to run a large spectrum of oil viscosity ... that's the point people are missing. If that wasn't true, the same engines in other non-CAFE driven countries wouldn't specify the whole range of viscosity in the OM.

In the case of vehicles that spec 8 and 16, then there are some specific design aspects, but not really for vehicles specing 20+ oils. Already mentioned why. It just so happens the push to use lower and lower viscosity is driven by CAFE. Like I mentioned earlier in this thread, what if CAFE didn't even exist. Do you really think engineers would be specifying 16 and 20 oils and operate the engine on the edge of adequate MOFT? I don't from an engineering viewpoint ... why would they when a little more viscosity headroom gives better protection.
Two other considerations in other countries. (Europe) They have very stringent air pollution regulations and the oil drain intervals are longer than here. Both favor a different formula oil package with the longer oil drain, the heavier oil needed. It is not the same market. Also the German Autobahn has no speed limit. Realistically our speed limit, oil drains, are geared to API rated oils.
 
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