read the oil "101" - thinner oil really?

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I'd like to say Thanks to AEHaas for providing the article on thinner oils. I took a leap of faith with my LS1 and used a thin oil for my ARX rinse. It was a short run just in case it didn't work out.

The LS1 orthodoxy is that they love, NEED, a thicker oil. GC, M1 0w-40, M1 TD 5w-40 are the most recommended oils. I tried Havoline DS 5w-30. The next-to-thinnest 30w on the list. It was an awesome test. Fabulous numbers.

Granted, there is such a thing as too thin. But this wasn't it.

Kudos to AEHaas.
 
M1 is a little over mid-pack in viscosity. Thinner than some, but not bottom of the pack. I presume that's the 30w you're alluding to, JAG.

Many in the LS1 community (at least the one at LS1Tech.Com) seems to believe that the engine will quickly die without an oil at least as thick as GC. Any oil defined as thin is hailed as a bad idea and "the thicker the better" is the clarion call.

I disagreed, but it's just more opinion without test numbers to show it works. The owner's manual calls for 5w-30 and 10w-30. I understand the large range of viscosity in the 30w lineup, and wanted to give proof that at least one LS1 wasn't going to die because of the use of about the thinnest 30w around.

Not earth-shattering in the least, but does challenge the convention wisdom of some.
 
From what I've read of LS1 engines, they don't all behave similarly, due to random variations of production. That can make a community of owners have very different ideas of what the engines as a whole need in terms of oil. I now understand why you said your results are useful for showing to the people who think the engines will quickly die on thin 30 wt oils. I am just surprised they have that opinion since as we've said, Corvette engineers spec'd M1 5W-30 for the engines.
 
Pretty much the gold standard for LS1 oil in that community is GC. Over time a few people shared the good luck they had with GC in their LS1s and it quickly became the favorite by word of mouth. Very few at that forum spring for oil analysis and don't know enough about oil in general to feel good enough to experiment.

The in-depth discussion and explanation of GC that goes on here does not go on there. GC is a thick 30w (despite the 0w part of the weight) so, therefore, LS1s must like thick oils. That's about the extent of most of the reasoning.

My idea is that GC is good because of its chemistry more than its viscosity. I got very similar numbers to GC with M1 TrSUv. Now I got potentially as good of numbers at the other end of the spectrum. Maybe. Don't know yet. But, it's just one motor out of many.

Though I truly don't have any personal experience with any other LS1s I haven't read anything about the manufacturing tolerances that would indicate they would be extremely different and require extremely different oils. But, I've been wrong before (don't tell my wife I said that...).
 
People say that a 50 wt oil at operating temperature is too thick and a 40 wt. is better for certain applications. The difference may be 5 cS. Yet on a hot summer day at 104 F a 0W-40 Mobil 1 would have a viscosity of 80 cS while a typical 15W-40 would be over 100 cS. Now the difference is 20 cS or more. The difference at 70 F, a typical start up day here in Sarasota, FL, is even greater.

So if a difference of 5 cS counts then certainly a difference of 30 or 50 cS should be even more of a problem. It is to me and that is why I advocate using a 0W-X instead of a 10W or 15W-X.

Lastly, the 75 F start up test in Dr. Schneider's article of recent was done only at ideal and low load. More, relevant data is forthcoming.

aehaas
 
Dr. Haas is a physician and surgeon. He graduated from the University of Florida with a degree in biochemistry with honors. He studied motor oils since high school where he did independent studies on this topic. He studied the properties of viscosity.
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His credential is very odd. I didn't think that a degree in biochemistry makes a person a physician and surgeon. I am a businessman at heart so I always look at things from a financial point of view. Even though I do my best to help with family businesses, I still keep my day job to ensure my immediate family has a stable income, good health benefits, and a peace of mind that there is a backup plan in case the businesses tank. Since Dr. Haas has very expensive cars, I assume he actually practice medicine. However, I don't see the correlation between medicine and oil study. These are two separate fields that need a tremendous amount of schooling and dedication a in order to achieve good living. I am totally confuse of why a surgeon studies oil and publish papers on motor oil. I am even more confuse that physician and surgeon's background is biochemistry and has extensive expertise in motor oil since high school. Either I didn't get enough vitamin today or my B.S. detector is working like a well oiled machine.
 
I never bothered to comment on it as the hero-worship seemed universal around here... but the whole situation strikes me as a typical physician god-complex. In this day and age, protected from competition and question by multiple professional organizations and a slew of governmental regulations, physicians deem themselves not ONLY qualified as the sole arbiters of life, death, and drugs... many have extended their sphere of influence into the BITOG-forebidden fields of religion & politiks. So motor oil is no big surprise.

This recalcitrant diesel mechanic is not impressed, and will continue to run 15W40 in the old beaters.
 
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Still wonder about the engine that is lugged up a long hill towing a trailer? maybe not on purpose but because the engine has enough torque and the transmission allows it. Rpm is low, load on the bearings is high. Does the slow turning oil pump and thin oil feed the bearing enough film thickness? I know suburu engines converted for aircraft will wipe the bearings on (thin) oils that are fine in a car.

Click to expand...
Well I can tell you that my Accord V6, which is spec'd for 5W-20, will only turn 2500 rpm at 80 mph in top gear, less at lower speeds. This isn't a torquey engine by any means but 2500 rpm at 80 mph should count as high load/ low rpm's. Anyway, Honda seems to think that 5-20 is sufficient for this car.

As for the guy who switched from 20W-50 to 5W-20 blowing his cam, I have to wonder whether this can really be attributed to the motor oil. Maybe it was something else or perhaps it was about to happen anyway?
dunno.gif
 
Dr. Haas is a plastic surgeon in FL. Oil flow through the engine can be related to blood flow through the body.
There are quite a few old posts when Dr. Haas first came to this site questioning him and the research that some folks did. I remember ekpolk checking up on him somewhat. Do a little searching & reading prior to publicly questioning a person especially when the information is on this forum.
 
The writings are fundamentally flawed. That is not to say that every part of them is wrong. He attempted a daunting task without sufficient education on a complicated subject so the result is not surprising.
 
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