He also says the 5W is 5 grade…..
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Confessions of a Recovering Thickie
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Patman
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It’s amazing how many people get that wrong. He seems very smart too, I’m surprised he keeps making that mistake.
He is smart, but all his videos are sponsored (you will recognize it) , so he cant start saying things that are not in line with his sponsors. The official statement from sponsors “always follow OEM recommendations”
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Mhmm. Then why'd you link his video?
Because he did say that thicker viscosity “can” provide more protection, yes, even the sponsored guy says that
For the general public he has a good 10,000 ft view. Us oil nerds can pick his info apart. His VM rant was a good example as we know with high quality base oils there could be little and in some cases no VM’s. I did like how he started getting into oil temperature and severe service like racing. It’s clear a higher grade can overcome adverse conditions and even some manufacturing shortcomings.
We also use to have a Pentastar engineer that frequented here. He made it clear CAFE was the reason for the redesign to 0w20. The engineering team was not happy and had to make some sacrifices especially in timing cain and component wear vs 30 grade.
And again it's worth noting that "more" heat is 2-3F going up a grade and worse MPG is usually 1-2%. But muh flow!
Yup, properly functioning cooling system will take care of those few extra 2-3F. Also, Honda DI dilutes oil with fuel and viscosity drops by 2 cSt+, this is where extra “safety margin” can come handy. I think of it as an insurance. The worst thing that can happen is you will spend few more dollars on gas…
Part of the GM recall (talked about at the 4 min mark) you failed to mention was that all the engines that didn't show signs of failure were now specified 0W-40, even all the new trucks on dealership lots. So essentially, GM just changed the oil spec from 0W-20 to 0W-40 for all of those multi-thoussands of trucks, even the ones in customer's hands and on the road. Why would the GM engineers do that if the inspection found there wasn't any issue found with the engine?
Then at time 4:30 he also talked exactly about what all the benefits are of more viscosity, like has been hashed in this thread in multiple ways. And he talks about how thicker oil in hydrodynamic lubrication "doesn't offer any wear benefit". But here's the clincher that he doesn't point out. Operating at the very bottom part of the hydrodynamic line on the Steinbeck curve is where you're running on the "ragged edge" like I've pointed out many times. Going thicker from that point and starting to get into the slight frictional increase part of the curve IS the wear protection headroom realm of operation.
He never address that thicker oil ADDS wear protection. And as pointed out in this thread, the small increase in hydrodynamic oil shearing friction, and the small increase in oil temperature are negligible compared to the added MOFT and the parts separation you get from more viscosity between moving parts. Plus, thicker oil will also give more MOFT and added protection on many of the parts that are in the mixed lubrication realm. So you seem to have missed a lot out of the video and only heard what you wanted to {"cherry picked"?) to try and justify that thinner oil is all beneficial compared to thicker oil. It's only beneficial for a hair more fuel economy and that's it. There is absolutely no benefit in terms of reducing engine wear, it only making parts run closer to zero MOFT because viscosity is key to producing a film of oil between moving parts.
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At time 8:15 he actually does get into exactly what's been discussed in this thread, and many other thick vs thin threads. He clearly shows that more KV100 gives more protection. And basically says use the right W grade (or better), and that going up in KV100 from the recommended is OK, but going down in KV100 could be "risky" - he means MOFT can go to zero. He even does show how thicker oil shifts the Steinbeck curve to the right (ie, that gives more wear protection headroom), but never just clearly says it outright. Pretty much everything he says and shows with the Steinbeck curve shows the benefit of thicker oil, but if people don't understand Tribology that well then they won't get it. He even gives the example of why thicker oil is used for severe use conditions like track use. Every Toyota OM even has a statement that thicker oil will give better engine protection in severe use conditions - those OM snip-it have been posted many times in these kind of threads.
If you never start the car below, say, 6-7C, is there any reason not to run a 20w50 oil, other than fuel economy?
His comments about CAFE are funny. Companies have cut costs on stuff in order to save way less than $60 per vehicle, lol. $60 per vehicle times 1M vehicles is a lot of money. Companies may give up some CAFE money when it makes sense, like when Ford bumped the viscosity up a grade on the Coyote in 2021. That bump up in viscosity was for good mechanical reasons, not "fuel economy". I wouldn't be surprised if GM eventually bumps up the viscosity to 5W-30 on new production engines.
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He talks about using Blackstone type UOA to see if thinner oil would cause more wear in his own car, but as discussed many times that kind of UOA is too insensitive to accurately see a wear changes like that, especially if only doing 1 or 2 UOAs. You have to build an on-going history of UOAs so see any major changes going on with the engine. He would have to get someone like the SWRI to do some very sophisticated wear tests on real time running engines, like shown back in post 123 of this thread.
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If the W grade supports use to that temperature then it should be fine. That's the whole reason the W grade was invented and defined by SAE J300.
I think you mean dimensions, not dementions.
Demention is what you diagnose your elderly uncle with when you find him in the grocery store without any pants on.
BWAHAHAHAHA!!
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It sounded like he was addressing this forum at many points.
Interesting that he stated that you can find studies to support whichever belief you have.
The same way that many of his points in the video can be "Cherry Picked" to do the same.
He knows that more viscosity gives more MOFT and therefore more parts separation and wear protection - but he skirts around it for some reason, trying to always justify to "trust the manufacturers" on oil specifications. He eludes in a somewhat round about way that more viscosity gives more protection headroom with his Steinbeck curve explanation and examples. The physics of Tribology never changes, no matter how someone twists it. Most of the studies on the subject matter overall conclude the same thing, that less wear is seen with more viscosity due to more MOFT - ie, shifting the lubrication operational points to the right on the Steinbeck curve, and that applies to the mix lubrication realm which can also benefit from more viscosity. More film thickness has happened from higher viscosity ever since a lubricant was between two moving parts. And all the information on journal bearings (ie, SubsTech/King Bearing) always shows way more benefits from thicker oil in journal bearing operation, like more MOFT and more uniform pressure distribution in the bearing. The positives outweigh the negatives by far.
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To me, it just comes across as “how thin can we go” and we do know generally the bottom limits are in the 20 Grade with typically 2.6 or greater HTHS. Thinner than that is new territory and requires specific formulations combined with manufacturing that allow for even thinner. This doesn’t mean it’s the optimal. It’s still about how close they can get to the line. Once again, we are back to square one: Going up a grade (especially when OM in other countries do not recommend the same as in the US) is really not going to cause harm other than potentially the small fuel economy reduction. As long as the “W” rating is suitable, the type of use and type of oil formulation seem to be more important than grade alone; as seen in the Engineering Explained video. Not all “W” ratings are achieved in the same way. Better base oils with naturally better cold properties do not require as heavy a dose of VM (and are there quality differences there?) and so aren’t nearly as susceptible to shearing during use. The small fraction of heat increase is negligible. If 2 or 3 degrees F increase running one grade thicker puts your engine into dangerous territory, you’ve got bigger issues. He even demonstrates on the curve that it’s merely hypothetical where 0w40 vs 0w20 would fall in the curve. I believe it’s far more likely that they exist more closely along the curve depending on the app and especially once we get back to one grade apart. It may wind up being purely insurance, but like all insurance when it’s needed it’s good to have. Maybe most people that baby their cars and don’t see severe service would see no benefit going up a grade. So, there isn’t a requirement one way or another. After all, most oils are merely recommendations. Many grades can be suitable. Finding the optimal is truly the context of these discussions here. You can hardly make a sweeping, blanket statement for everyone. It goes back to the “as thin as possible” , but “as thick as necessary”. What happens to slightly thicker oil in operation relative to this stribeck curve depends on the engine and the specific use it sees. So, of course the inverse of “as thick as possible” isn’t optimal either by itself. At what point does going up to a grade meant for cars seeing the track; such as a jump from 20 to 40, potentially be less than optimal for said vehicle driven on the highway at steady speeds that never sees oil temps climb as seen in track or towing in the mountains for example?
Going up a grade from any manufacturer's "recommendation" of a xW-20 or less is adding some engine protection. The small oil temp increase and super small decrease in fuel economy are hair splitting and outweighed by the potential benefits. It's that simple, and many technical sources based on Tribology backs that up. If people don't believe that, then they need to do a lot more study on the subject matter and prove it to themselves. Sometimes a flat Earther needs to go into space himself and see with his own eyes that the Earth isn't flat. 
Is thicker oil always "needed" ... no, but in some cases it certainly is based on use conditions. But again, even if the more demanding use conditions are rare, going a bit thicker it's all about added headroom insurance to ensure there's a bit more film thickness between moving parts to reduce wear over the long run. I'm not going to change oil on the side of the road if I want to beat on the Coyote - it's got 5W-30 now, way before Ford decided to go there in 2021, and would get 0W-40 for any hard track use. More viscosity is also good if fuel dilution is a big factor on some engines.
And as seen many times, and even in this thread, OMs for the same engines in other countries will specify a whole range of viscosity from xW-20 to xW-50. Engineers would not allow that in the OM if they knew it's going to "harm" the engines. What harms engines most are: 1) Using the wrong W grade for the start-up conditions, and 2) Lack of lubrication supply to moving parts due to design or mechanical issues, including improper materials and/or heat treating. But lack of adequate MOFT can be described as "lack of proper lubrication".
Is thicker oil always "needed" ... no, but in some cases it certainly is based on use conditions. But again, even if the more demanding use conditions are rare, going a bit thicker it's all about added headroom insurance to ensure there's a bit more film thickness between moving parts to reduce wear over the long run. I'm not going to change oil on the side of the road if I want to beat on the Coyote - it's got 5W-30 now, way before Ford decided to go there in 2021, and would get 0W-40 for any hard track use. More viscosity is also good if fuel dilution is a big factor on some engines.
And as seen many times, and even in this thread, OMs for the same engines in other countries will specify a whole range of viscosity from xW-20 to xW-50. Engineers would not allow that in the OM if they knew it's going to "harm" the engines. What harms engines most are: 1) Using the wrong W grade for the start-up conditions, and 2) Lack of lubrication supply to moving parts due to design or mechanical issues, including improper materials and/or heat treating. But lack of adequate MOFT can be described as "lack of proper lubrication".
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