Exactly. Multi-viscosity oils defy the laws of physics. You got it!wait, I thought oil gets heavier as it heats up.
doesn't 5W30 mean 5 weight when it's cold and 30 weight when hot. Isn't 30 higher than 5?
Will Thinner Oils Damage Your Engine?
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Thatās quite a load of half truths and outright misunderstanding in that video.
Even if he does use the word āmoron(s)ā. Everyone should know their limitations and the extent of their knowledge, and try to work within those confines. That way you wonāt end up looking like a moron.
Calling other people āmoronsādoesnāt qualify you as a genius...and it certainly doesnāt make you right...
Maybe and maybe not. Everyone has an opinion and the end of the day, you need to do you. I donāt t want people to be scared into believing that xW20 oil is bad for your engine or you will have damage over time. Iāve seen the light when my Accord (which I bought brand new) is about to hit 300,000 miles running 5W20 and my Tundra Is about to hit 200k running 0W20 with heavy towing and I live in South Texas. A lot of great opinions here. I always say careful whose advice you buy, but be patient with those who supply it. You can learn a lot from listening and be able make a decision with more knowledge than you had before. I can say I have learned a lot. Even from these āfellersā.
MolaKule
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When he traded it in it had 210,000 miles on and not even a valve cover had ever been removed. Nothing wrong with the metallurgy in that one.
MolaKule
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TD did not have any formal training in Tribology or in any other related scientific field so he could not tear apart any argument with any response.
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Well, in truth the question proper should be rephrased because the correct answer is yes and no depending on a host of conditions and qualifiers unique to a specific vehicle.
Its overly broad and general as stated
Its overly broad and general as stated
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Even though I prefer thicker oils and you do not, this comment of yours is one I really respect.
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But as a generality one can say yes, no?
Put it this way, if manufacturers weren't mandated to squeeze every last drop of fuel efficiency, would they be spec'ing thinner and thinner oils?
At the same time, thicker doesn't mean it will protect better. I'm sure you can't just put 20w50 in an engine designed for 0w20 and have it be better either.
Ford specs adjustments referred to 5w 20 pcmo for belt driven cams . 5w 30 pcmo for chain driven cams per my friends in Dearborn
Pure speculation on my part. I guess they had issues with timing chains in some applications running the 5W20 and bumped it up???? Either way it sounds like they might have been addressing warranty claims, or potential warranty claims??
Ford never specd Full syn pcmo in their sump back then always , timing chains were an issue then . Most GF 6 will address this . Plus Dexos 1 gen 3 will be more up to date '
while reading a link from this forum to machinery lubrication on the importance of BETTER oil filtration + NOT lkeeping todays MINI filters in TOO long it was noted the lesser oil film ow xxW20 oils is LESS protective as dirt particles are more likely the same size as the film + WEAR con occur for this reason!!!
I agree, as always time will tell.
Of course it does. A thinner oil film allows smaller particles to cause wear. It's not "0W" oils but the grade that causes this.
Your first question is easy to answer. What benefit except greater fuel economy do you get with thinner oils? Manufacturers may have done so without the mandate, but increased fuel economy is the only benefit.
And for the second statement, why couldn't you if the winter rating was appropriate for the expected starting conditions? Engines can be designed to facilitate or even permit the use of thinner oils but that does not preclude the use of thicker ones, nor does it make them damaging. Just how big does anyone think these oil molecules are?
That's very difficult and the best way I know to answer you is to quickly outline the process as I would design machine "X" ( the process doesn't really change)
I design a mechanical joint against a load range with a requirement to last 1,000,000 cycles ( that's a normal design requirement, maybe some more things). This will define expected efficiency losses, heat, relative velocities (RPM etc.) and all that
So I select the metallurgy, dimensions, finishes, treatments to achieve this. ( second step is to build it)
In parallel, I select the best tribological regime and develop whatever MOFT I think I need- the lubrication regime is designed around this.
After all that is done, I have a mechanically fixed system.
This is what people are referencing when they say a machine is "designed" to an oil- its not actually designed to the oil, the oil is selected based on other constraints. ( which are usually fixed)
Then the level of precision/over strength factor (s) is considered ( alternative selections based on different load profiles)- you have a lot more variance say with a car engine than a machine spindle traveling at 100,000RPM with .000000001" tolerance.
So, in light of all the above considerations and what the machine is built to- its not a good idea to arbitrarily make the statement either way because there is a range of acceptable based on a set of requirements.
"generally" it is safe to say that as long as the lubrication regime will provide the film strength at the given load- you are fine.
Knowing where those lines are can be the tricky part. There is a range of acceptability in all machines but it cant realistically e stated as a general allowance because of all the considerations involved.
I have had many gear boxes that require additions such as kidney or cooling loops or adjusted service factors when application and lube regimes are significantly changed.
I have had others where there was no appreciable difference or was within the overall design of the box.
I say no. As the question is phrased, thinner oils will not damage your engine.
Going one step further, thinner oils should and will not cause increased wear in engines with specs saying to run those oils. If a manufacturer takes a engine that was originally running on 5w30 ( a CAFE oil itself) and back specs it to 0w20 without any changes then one might ponder that.
Many of the modern engines these days run on 0w20 very well as they were designed with that grade in mind.
CAFE has been around now for almost half a century. That is longer than BITOG has been in existence. It is the eternal argument here.
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