This study discussing wear as a relative function of viscosity is w.r.t. the bearings, correct? Not the pistons/liners?
This study discussing wear as a relative function of viscosity is w.r.t. the bearings, correct? Not the pistons/liners?
That, and no one drives around with their sump perpetually at 304 degF while running 6,000 rpm with an unbalanced load on the crankshaft ... the test conditions used to bring out the HTHS importance.Correct. The focus of this study was on the bearings alone.
Also note that this study was date 1998. The comparison included bearings with a lead component which nobody uses anymore in passenger automobiles.
What is interesting and often forgotten is the computer cars with more precise fuel metering and timing via knock sensors are what allowed the thinner energy conserving oil and good engine life but as in all things we are finding the weaker links. Cujet nailed it again.And for no reason at all, modern cars started burning oil and destroying timing chains.
But they are still recommending 15W40 in Sri Lanka and Lichtenstein, so there’s that. Those engineers are a slippery bunch.Australia is recommending 0W-20 and 0W -16 now. The times are changing.
From the Austrailia owner manual screen images I've seen posted on BITOG, Australia owners manuals are recommending 0W-16, 0W-20, 5W-30, and sometimes 5W-40 on the same page, leaving it up to the owner to choose one of those recommended viscosities.But they are still recommending 15W40 in Sri Lanka and Lichtenstein, so there’s that. Those engineers are a slippery bunch.
Clearly one size doesn't fit all, and the engine won't self destruct with a "thicker oil" in the sump as some would like you to believe.From the Austrailia owner manual screen images I've seen posted on BITOG, Australia owners manuals are recommending 0W-16, 0W-20, 5W-30, and sometimes 5W-40 on the same page, leaving it up to the owner to choose one of those recommended viscosities.
HTHS of 2.6 is a sweet spot, which is where 0W-20 oils start out as virgin oils, and which seem to have widespread support on this forum as being safe for long term use. You might be right about HTHS > 3.5 as being unnecessary.I have actually learned something here. Again, I will still look for as thin an oil as I can get during the start up period (kinematic viscosity). This is because I feel it is best to get more flow before my engine goes into bypass. And I like high RPM. At my usual start up my oil is in bypass at 3,000 RPM by the time I get out of my neighborhood (redline = 9,000 RPM). I feel oils with a HTHS of say 2.5 is fine for my engines.
So the mission will be to find the lowest viscosity at 40C while the HTHS is around 2.5 or so. Looking for a 30 or 40 or 50 grade oil, as many seek, is not in the equation. Now I feel those numbers are essentially useless. Higher grades do not necessarily guarantee higher HTHS, you have to look at the actual specs (as many here already do). I do think that insisting it is >3.5 is unnecessary. The real number, and it has headroom in my book, is 2.5. I reserve the right to lower this number with forthcoming oils however...
I do think the data has some value. It indicates that HTHS is something to look at. I admit this. But I believe that a HTHS of 1.8 or even 1.6 is probably OK for most modern engines using modern lubricants. Though personally I might go for slightly higher values as my cars often have fuel dilution issues.
Ali
I'm not sure oil analysis from companies like Blackstone is really that accurate.I do not want any wear either. I have shown that 20 and 30 grade oils in a Ferrari Enzo results in essentially no wear (no tack use though). The spec'ed oil is a 10W60. The testing was with engine analysis and oil analysis.
Ali
Well dang what are people on the Internet gonna have to argue about now? Thanks Toyota. Inconsiderate.From the Austrailia owner manual screen images I've seen posted on BITOG, Australia owners manuals are recommending 0W-16, 0W-20, 5W-30, and sometimes 5W-40 on the same page, leaving it up to the owner to choose one of those recommended viscosities.
Yup, HPL's new monograde Euro 5W-20 has an HTHS of 3.27cP (might as well round-up to 3.3), heavier than most ILSAC 5W-30's. My named 0W-20 is 2.7.People often think of viscosity as - 20, 30, 40 and 50 when in reality it's 21,21,23,24....
You can find some 20 grades that have a HT/HS of 2.8-3.2.
Time fixes all. Instead of looking for oil to fix hardware issues maybe some here should concentrate their minds on choosing reliable engines.Before it was total'd in a wreck, my wife's 2005 Grand Marquis would beg to differ. After a quater-million miles, the engine ran great, had no major maintenance issues, and didn't consume oil. My 2007 Grand Marquis also did just as well.
The ol' 4.6L mod-motor is very easy on oil in the 2v configurations. All on 10k mile OCIs, 5w-20, mostly conventional oil. Some engine designs are very robust, some not. 281 cubes with only 225 hp doesn't exactly qualify as high-stress ...
The "dino" oil in this UOA series was the Rural King brand; about as cheap an oil as one could buy back then. I'm sure it's HTHS rating was not impressive by any means, though I'm not sure what the actual value would be, but at $1.29/qrt, there little reason to think it was "robust" oil. And yet, it did a fine job protecting the engine, even out to 10k miles repeatedly.5w-20; Ford 4.6L engines; UOA testing
Originally Posted By: JLTD Guess I need to run the Amsoil OE I just bought for MUCH longer than 5000 miles! Make it 10k at least....and sample and leave it in. If you do a lot of highway miles.... you might be good for 20kbobistheoilguy.com
I've seen 5w-20's all the way up to 10w-40's all do well in the old Ford mod-motors (2vs). That engine series just isn't susceptible to viscosity/HTHS concerns in normal use. That engine series could not care less what lube is used, as long as it's reasonbly appropriate for the application. Clearly, some "thin" oils do quite well in some "good" engines.
However, a poorly made lube in a poorly designed/built engine will never end well. There are other engines that don't fare well at all, regardless of what oil is in the crankcase. Some are just trouble prone. And no amount of HTHS would save them.
As both lubes and engines have improved over the years, I think the HTHS topic has lost some of it's zing; it's just not as important as it was decades ago.
I was surprised to learn that most supercars regardless of brand never make it to 100k miles. The Quality and QA testing just isn't there, with so many parts made of cheap plastic and even the car bodies getting severed in half in minor car accidents. And fixing even the simplest things like replacing most parts requires dealer sold OEM parts, which instead of costing a few hundred dollars cost 7,000 dollars. You would think if you're going to spend $200,000 on an Italian super car, you should get a high quality car that will last longer than a cheap Japanese economy car costing 1/10 the price. But the opposite is true. So if I could ever afford to buy a super car, it would be an Acura NSX, so that at least you would get Honda's reliablility instead of some Italian supercar maker's reliability. If you google: What is the cost of an oil change for a Bugatti Veyron, the answer is $21,000 for the oil change. For the price of that oil change, you could buy a new Honda Civic or Toyota Corllla and get the whole car. Even if I were a billionaire, I think I'd pay my local mechanic $30 for his labor and give him 5 quart jug(s) of synthetic oil and Fram Ultra oil filter bought at Walmart.Time fixes all. Instead of looking for oil to fix hardware issues maybe some here should concentrate their minds on choosing reliable engines.