OCI, not when but why?

[KARNUT]

I got you all beat. My wife’s Acura Intagra Type R. gets once a year oil changes at the dealer. Once a month I drive it about 20 miles. 

[customboss]

17 hours ago, PunchT37 said:

I`m very old school. My OCI is the dipstick. Then comes my eyes, my nose, then my fingers. My brain kinda kicks in on my vehicles that sit most days in the year. I change it after 8 mos or so,no matter how little miles.

 

Mileage wise, I think 4600 is my record. I am also a "thicky". It has worked well for me all this time. I`m 61.

 

I run all my engines to the red line. Many times. I have never lost a bearing. BUT, I don`t rev any engine when cold.

 

I started mechanic work for a living in 1985. So, I`m set in my ways.

The key is you have experience and training and pay attention. Checking the oil more than once a year like many of our digitally locked younger members means you see problems BEFORE they crater your ride. 

[PunchT37]

12 minutes ago, customboss said:

The key is you have experience and training and pay attention. Checking the oil more than once a year like many of our digitally locked younger members means you see problems BEFORE they crater your ride. 

Digitally locked. LOL

[PunchT37]

 

 

One could say, lazy, cheap, and lack of prudence. Even though they are cheap, a little prudence can save them a lot of money. How ironic?

 

I`m cheap too. But prudent. That`s why I`m just now getting ready to order a 2025 Silverado LT. Then I can rest my 2000 Silverado. I won`t trade it though. It`s still in very good condition. LS, 5.3 LM7, 2wd, 3.73 with G80, Z85 suspension, etc.

 

 

 

Edited August 15, 2024 by PunchT37

[Grumpy Bear]

Think we're missing the point. People treat this subject like the machine can and will respond to manufacturing goals, recommendations, Government regulations, Tic-Tock trends, third party business plans, your likes, dislikes, dogmas, experiences, wishes, beliefs, financial situation, education, needs, social status or the group consciousness. It does not care. It is incapable of caring. It's a machine. It is governed by universal laws. Period. Can't even care if you like that or even agree with it. You can't impose your will on it. You can't intimidate it. Embarrass it. Bribe it. Convince it. Reason with it. You can't outsmart is, outthink it or redefine those laws to suit your wishes.

 

What can be done is to apply yourself to understanding the laws that it is subject to and do you best to align your program with that.

 

Or not.  

[Grumpy Bear]

Have a cuppa and enjoy the fact I'm not going to add comments to this.

 

https://www.machinerylubrication.com/Read/562/oil-change-filter-sensors

[diyer2]

 

[Grumpy Bear]

On 4/16/2025 at 7:59 AM, diyer2 said:

 

 

 

Question. How do you think a medical diagnosis taken from a laypersons reading of Woman's Health  or 16 Magazine stacks up against a Harvard Medical PhD? Or anyone in the top 50 on this list?  https://edurank.org/medicine/

 

I'm going to take a step off a cliff here. You chose both your oil and your OCI based on???????????????????????????

 

Marketing!? Vast personal experience?

  

 

Hey, most people do. That is a boat rowing downstream. Make your argument with DATA and not your gut, then you will get my attention and can post your Demi Lovato wise crack. 

 

 

[diyer2]

It's called practicing medicine, enough said. 

 

I chose my oil and OCI's from experience.

 

I'm glad you're scientific research works for you, my experience works for me, no need to keep proving it works. Better things to do.

 

 

[Grumpy Bear]

1 hour ago, diyer2 said:

It's called practicing medicine, enough said. 

 

I chose my oil and OCI's from experience.

 

I'm glad you're scientific research works for you, my experience works for me, no need to keep proving it works. Better things to do.

 

 

 

Seems I haven't. To keep proving is an acknowledgement that it WAS proven and that proof was accepted as true and now I should move on to something other. How gracious.  And yet you, in he face of the facts, prefer to cure leukemia with leaches. But wait, that isn't good enough. You want everyone that disagrees with the use of leaches to refrain from hearing, seeing, or speaking. Censorship is your gig here?  

 

How about you just change the channel? Is that a workable solution? No one forced you to read the link and I didn't comment on it. I offered it. We already have joke thread to post your funny videos too. 

 

 

[Grumpy Bear]

API SQ

 

https://www.fuelsandlubes.com/fli-article/api-sq-category-advances-amid-debate-over-sulphated-ash-limits/

 

And what would this have to do with OCI length?

CHANGE

 

API service class SC was on it's way out when I started driving and maintaining. 

 

https://www.sae.org/publications/technical-papers/content/670019/

 

And what would ring face geometry and facing type have to do with OCI length? 

CHANGE

 

Ditto aluminum motors and the OEM use of Roller Cams and Spray bores and....and....and...

Oh and not knowing what tech is in what motor until way to late! 

 

What experience should have taught one that was paying attention was; leaning on it can put your equipment in the boneyard. 

 

Somewhere along the way we got this stilly notion that the OEM's and the API and the Regulators have our EQUIPMENTS best interest in mind and that they never lie. IF one believed that then they put their head down and swallowed the extension of thought that every change was BETTER for the equipment. 

 

YOU HAVE TO KEEP PROVING IT BECAUSE IT KEEPS CHANGING!

 

 

 

Edited April 19, 2025 by Grumpy Bear

[Grumpy Bear]

On 8/16/2024 at 12:12 AM, Grumpy Bear said:

Think we're missing the point. People treat this subject (OCI) like the machine can and will respond to manufacturing goals, recommendations, Government regulations, Tic-Tock trends, third party business plans, your likes, dislikes, dogmas, experiences, wishes, beliefs, financial situation, education, needs, social status or the group consciousness. It does not care. It is incapable of caring. It's a machine. It is governed by universal laws. Period. Can't even care if you like that or even agree with it. You can't impose your will on it. You can't intimidate it. Embarrass it. Bribe it. Convince it. Reason with it. You can't outsmart is, outthink it or redefine those laws to suit your wishes.

 

What can be done is to apply yourself to understanding the laws that it is subject to and do you best to align your program with that. 

 

Seemed worth repeating. 

 

Everything I said above that can not be done to a machine; can be done to a human.

 

[Grumpy Bear]

Thoughts about OCI by Data

 

 

I bought this unit new. I had the dealership change the oil before it left the lot; 24 miles. Then again at 1,000 miles, 2,982 miles then 7,463 miles and upon the next interval at 11,250 miles, a number divisible by 3,750 miles, the severe schedule, I pulled the first UOA sample. The first data point in the graph. Since that first sample I have held the interval and the oil, down to the batch number, a constant. 

 

The blue line is the percentage of the VOA value and that number is one of my condemnation points. I'm not going to argue the validity of using TBN as a guide but I will explain the idea. 

 

There is a correlation between TBN v TAN v Wear metals. It's been studied to death. 

 

 

In this graph above wear metals are not normalized, they are cumulative. This is an important distinction as one can see that early on the increase in iron is LINEAR as acid value increases and base number decreases. At about the 60% retention rate (July) the rate of wear starts to increase, non-linear. And the rate per unit/time/hours/miles CONTINUES to increase until the TBN reaches about 1 mg/KOH/g. At which point the rate is nearly vertical. That value is what the labs like Blackstone use as a condemnation point. Yea...that horse left the barn a few months ago. What they are saying is that keeping wear in check and linear is not important and it's okay to wear at an accelerated rate. Why I'm not going to argue that stupidity. What I am going to say is the for my equipment this is not acceptable. 

 

Okay, walked that dog long enough. Back to Graph 1. Wear metals (Iron) in the example motor is falling along a Power Curve with an R of 1, while TBN residual is rising quite along a linear path, also R near 1. (That graph is not shown). 

 

An impatient me would start increasing the OCI now seeing two equal and linear increased in residual and a perfect rate drop in iron as I have a definable pattern at this point. Problem with doing that right now is that it would uncouple wear rate from residual increase so the patient me will wait until one or the other flattens and decouples naturally. I hate missing an opportunity to learn something useful. 

 

 

This unit is now setting at 21,000 miles and still in the first box of the above studies to death wear pattern graph and this graph tells me that wear and TBN residual WILL decouple and when it does I will start lengthen the OCI and continue to monitor for the next two phases of wear. 

 

In box #1, the wear in, the OCI was short, very short and stayed short until wear RATE peaked, first 500 - 1,000 miles. The next few were short but increasingly longer settling on the OEM severe schedule as a base line. Have to start somewhere, an now riding the declining portion of that first phase. 

 

So couple of points. OCI isn't constant through a motors life, or shouldn't be. It isn't defined by normalization or statistical sets of data generated by the OEM or some University study trying to find Joe Average or some EPA requirement for waste. It isn't found by trail and ERROR. Lean from others mistakes, don't repeat them. 

 

I've said often. OCI is FOUND. 

 

***************************************************

 

You can not find your marks by trading oils or even batches of oils and you can't find them without points of reference. 

 

Yet EXPERTS with allot of letters behind their names have suggested to me that I should try oil XYZ and maybe ABC. That the OCI is to short and the TBN/TAN relationship is 'out dated' and "irrelevant" due to vast improvements in blah, blah, blah. 

 

Data says Otherwise

 

There is a reason I'm Grumpy

 

[Grumpy Bear]

Iron Curve for above Information. 

(That is...same motor, same data. No cherry picking going on.)

 

Declining slope of zone #1 of the wear curve.

That is, the last graph of post above.

Normalized in ppm/K miles

 

 

Declining wear rate with an increasing TBN residual = improved power cylinder sealing. ALL motors need running in. Fact is, you can't avoid running in. You can work with it or against its best possible outcome but wear in or wear out it will. This curve is different for every unit and would be different for the same unit under different supervision and/or other lubrication choices in same supervision. 

[Grumpy Bear]

Wear RATE

 

Rate of wear. Wear verses unit of time. I think most people look at their wear metals and see them as isolated points. There is some value in that if you are using the proper mental filters but in general it is far more useful to look at them as trends. Even more so is to look at trends that have been isolated from induced interference. Noise verses signal. And there are two types of noise. Natural system variations and as I just said, noise that is induced. We have more influence over the later.

 

Use the same lab. Use the same sample collection method. A big one, use the same oil lot and get a VOA so you can subtract what is in the oil from what the motor produced. If you use random lots that have varying backgrounds then you will get varying results that make the trends harder to see and take longer to define. Illustration: 

 

 

 

The red dot is an isolated data point and as such no trend is possible and all that can be said is that this point is below the average acceptable OEM average of 5ppm/1K miles. Even then, unless I told you this is this motors universal average you wouldn't know what part of the motors life curve you were looking at.

 

White dots and orange trend line was generated using a different lot and even a different recipe from the same vendor in the same SAE grade. Both Mobil 1 products of 5W30 but differing bases and add packages. The dots are the noise.

 

Green are all the same product from the same batch in consecutive samples of the same length. Change of the abnormal type will be easier to see and seen sooner. 

 

A few things to keep in mind which go to some other points earlier made. Wear metal testing, regardless of the exact method used, are a 'slice' of the spectrum. These test do not cover the entire field of size but use of the same lab which insures the use of the same method will insure the minimum in induced noise. 

 

So what does this have to do with OCI length? The fact that it is found by testing and not assigned by some need that is outside your machines best interest. That does not mean that those competing interest will not provide a personally acceptable result. They will. They will not however provide the best results. 

 

As you can see from the chart all three viscosities will provide protection that limits wear RATE to under 5ppm/1K miles once break-in is complete. But there is quite a difference in absolute rate and in the methods or circumstances used to generate your confidence in the data. Common sense will tell you that the faster you eat a cookie the quicker it is gone. Higher rate of wear = fewer miles to wear out. It is that simple. 

 

In the end, that is what scientific method is about. CONFIDENCE in the data. 

 

Edited May 22, 2025 by Grumpy Bear