Thin cleans better, allows longer OCI than thick!

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If you spent some time on BITOG, you must have got the idea that there is no such thing as the best oil or whether thin is always better than thick or vice versa. For example, we know that thicker oil usually tends to provide better wear protection.

One question I always wondered about was the relative base-oil quality of the thinner and thicker base stocks within the same base-stock family. In other words, is a thinner Shell Pearl GTL base stock of higher or lower quality than a thicker Shell Pearl GTL base stock?

My base-oil-quality index (BOQI ~ 1/CCS/NOACK), which has turned out to be extremely robust and useful, has long predicted that thinner base stocks are superior to thicker base stocks in base-oil quality. 0W-20 scores higher than 5W-30, which in turn scores higher than 10W-30, which in turn scores higher than 15W-40 in BOQI. Base-oil quality (BOQI) primarily relates to an oil's oxidation stability, which determines the OCI length and engine cleaning.

However, without actual data, we wouldn't know if this is an artifact of BOQI or thinner base oils indeed have higher base-oil quality (less oxidation). I've finally found a scientific study, which clearly demonstrated that thinner base oils indeed have more oxidation stability and leave less deposits and allow longer OCI's than thicker base oils.

yaYyEfFLTHy9dg9yysFehPQDKYwwGbcc4m5eirR8GaLKvXzDf1DCfPC8wFulBOG__RJaZDl4P_3R16FS3avN4bzbFiClAJGvG9z1YOOzc4_mTfwcePKGZ2flA-paw7bS9Sa0Nt3nxHL0z4LkQlh3xgFXAfszWKB908GIjVCwitVbPfGwH3gjIfM_XgyqCxIZ73dg53Udrza49vYSZIjBxB5AiJXL0NUKgHRWpxIh-Zmd3uHEvFYEqO77tdtyhOKCEGkpZZ0UALSUPl5ubeMo54YLCfBkMOyElYSvKHLjNtXQptIDt-F5a29kAxti2REaHmsWy6S8GBLLhOzKlE-CUYlA7MnGLHxzefo62i33t39UsRSazg6pT3AWaTz8TyXCkHZvryTV_lonjTWs0h__3Vj00Et5eNHPvXGdg9a2NHaaQYTihXh6bQyXEP0TDeAGQ0hD8-MUwZsFnT94GCKBZxIZpvGhRU6wOpYHsvhWFgnGvZfIyf6IAGqiT54dOqekBp8GQfbUsvET4eVNdga0utXhmQGK6KuvuqZdkEQqULMBs7WtIQX3SEl8kd9VDeLN8ByYfxXmnBtsIZ14vrt7pHvEtmFFijK-Ec1dRQXp=w656-h394-no


Effects of hydroprocessing on structure and properties of base oils using NMR (PDF link)

In stark contrast to almost everyone's intuition on BITOG, within the same base-stock family, lower the NOACK (less the evaporation) is, the more the deposits the oil leaves on the engine and less the OCI length are! So, low NOACK by itself can be a bad thing!


If you are concerned about the base-oil quality, low NOACK by itself is not the answer and it can ironically work both for the base-oil quality and against base-oil quality. If you consider the NOACK and CCS together as in the BOQI, then you will get a more definite answer.

As an example, Pennzoil Platinum 0W-20 (higher NOACK) would result in better engine cleaning and allow a longer OCI than Pennzoil Platinum 5W-20 (lower NOACK) because they are made from the same base-stock family (Shell Pearl GTL) but the the 0W-20 has a thinner base oil, which results in less oxidation and deposits.
 
I'll take deposits where they accumulate in an accessible to oil area rather than in places where it accumulates by evaporation and clogs things up that won't be washed off by new oil fill.
See? there is a counter to every proposition.
Now, convince me.
 
Originally Posted By: Dyusik
I'll take deposits where they accumulate in an accessible to oil area rather than in places where it accumulates by evaporation and clogs things up that won't be washed off by new oil fill.
See? there is a counter to every proposition.
Now, convince me.


I have used 0-20 oils for years now in my last three engines, and I never get deposits any place for any reason.
 
Originally Posted By: tig1
Originally Posted By: Dyusik
I'll take deposits where they accumulate in an accessible to oil area rather than in places where it accumulates by evaporation and clogs things up that won't be washed off by new oil fill.
See? there is a counter to every proposition.
Now, convince me.


I have used 0-20 oils for years now in my last three engines, and I never get deposits any place for any reason.
M1 is a very "clean " oil. Also you do reasonable oil change intervals.
 
If that's the case, why is it that Japanese manufactures lobbied the API to have 0W-20 exempt from passing the TEOST test? Is it a coincidence that a majority of manufactures from Japan that specify 0W-20 oils are involved in class action lawsuits for oil burning due primarily to ring deposits?

Ed
 
Originally Posted By: Gokhan

One question I always wondered about was the relative base-oil quality of the thinner and thicker base stocks within the same base-stock family. In other words, is a thinner Shell Pearl GTL base stock of higher or lower quality than a thicker Shell Pearl GTL base stock?
.


You’ll first need to define “quality”. While busy with that, you may notice that it depends on what you’re trying to achieve. A thin base may be great in formulating a 0W20 but quite lousy if your purpose is a 20W50. And the other way round.
 
I encourage anyone to read the article, and understand what that table means.

PN - Paraffinic Neutral besestock (9.9Cst) - 96VI
HPN - as above, but hydrogenated (9.7Cst) - 99VI
NN - Napthenic Neutral (5.05Cst or thereabouts) - 89VI
Next three (HA1-3) are successively hydrogenated aromoatics from cracker stocks)
HA1 - 5.9 Cst - 3VI
HA2 - HA1 hydrogenated 5.1 Cst - 6VI
HA3 - HA2 hydrogenated 4.2 - 20VI
PAO - Polyalphaolefin 5.5Cst - 155VI



The testing is about the hydrogenation of basestocks. ONE of the parameters is deposits LEFT in a thin film test.

The conclusions that Gokhan is drawing regarding
* this paper giving any indication of CLEANING ability (the article mentions lack of solubility with some of the basestocks...incompatible with "cleaning".
* this paper giving indication that thinner basestocks "clean" better than thicker

Is specious...then to draw it into the already flawed BOQI is ridiculous.

Especially when the cleanest with regard to leaving deposits were those with the highest NOACKS, and would therefore have the worst BOQIs.

WOW...
 
Oil selection cannot be done looking at one single aspect, if what you're saying is that thinner oils because of their usually higher quality base stocks have better oxidation characteristics that may be correct, but if i went right now and poured ta full syn 0W-20 with great oxidation characteristics in either of my two cars i'm sure they'd be clean as heck but they'd rattle themselves to death
laugh.gif
and the main bearings would not be happy.
 
I don't think the three basestocks with VIs of 20 and below would be considered even "reasonable", let alone superior
 
Originally Posted By: edhackett
If that's the case, why is it that Japanese manufactures lobbied the API to have 0W-20 exempt from passing the TEOST test? Is it a coincidence that a majority of manufactures from Japan that specify 0W-20 oils are involved in class action lawsuits for oil burning due primarily to ring deposits?

Ed

The reason for the TEOST exemption was that they wanted to load their 0W-20's with moly, which leads to deposits. It has nothing to do with the base oil or viscosity.

Japanese engines are the most reliable out there, period. Are you talking about the 2AZ-FE engine, which is only one exception, which actually recommended 5W-30?
 
PP is going to use GTL regardless … huge investment to recover … M1 EP in 0w20 has twice the PAO compared to M1 AFE 0w20 … AFE not recommended to 15k (but some have done that) …
 
Originally Posted By: Shannow
Especially when the cleanest with regard to leaving deposits were those with the highest NOACKS, and would therefore have the worst BOQIs.

You didn't read and understand my post.

The article clearly states that there is an inverse correlation between the evaporation and deposits.

BOQI ~ 1/CCS/NOACK

You don't get a high BOQI just because NOACK is low. That could mean the oil is thick, which could result in a high CCS and low NOACK. In other words, you could have a thick Group I with low NOACK and BOQI would be low despite the low NOACK. This is the magic about BOQI. It takes into account both the viscosity and NOACK and it actually works for giving a fair estimation of the base-oil quality, which is related to the oxidation, deposit formation, and allowed OCI length.
 
Originally Posted By: Gokhan
The article clearly states that there is an inverse correlation between the evaporation and deposits.


Point me to that statement please...
 
Originally Posted By: Gokhan
You don't get a high BOQI just because NOACK is low. That could mean the oil is thick, which could result in a high CCS and low NOACK. In other words, you could have a thick Group I with low NOACK and BOQI would be low despite the low NOACK. This is the magic about BOQI. It takes into account both the viscosity and NOACK and it actually works for giving a fair estimation of the base-oil quality, which is related to the oxidation, deposit formation, and allowed OCI length.


But the paper has ZERO mention of the CCS...but you claim that the BOQI and the paper prove each other in some sort of circular argument.

What do you think the CCS of a "thin" oil in the context of the paper and a Viscosity Index of 3 is going to indicate in terms of CCS ?
 
Originally Posted By: edhackett
If that's the case, why is it that Japanese manufactures lobbied the API to have 0W-20 exempt from passing the TEOST test? Is it a coincidence that a majority of manufactures from Japan that specify 0W-20 oils are involved in class action lawsuits for oil burning due primarily to ring deposits?

Ed

A little more explanation:

The reason for the TEOST exemption was that the Japanese manufacturers wanted to load their 0W-20's with many hundreds of ppms of moly and did so in the past (ADEKA SAKURA-LUBE), which leads to deposits. It has nothing to do with the base oil or viscosity. Today newer forms of moly such as the Infineum trinuclear moly work at only 75 - 100 ppm in achieving the same friction modification.
 
Originally Posted By: Shannow
Originally Posted By: Gokhan
You don't get a high BOQI just because NOACK is low. That could mean the oil is thick, which could result in a high CCS and low NOACK. In other words, you could have a thick Group I with low NOACK and BOQI would be low despite the low NOACK. This is the magic about BOQI. It takes into account both the viscosity and NOACK and it actually works for giving a fair estimation of the base-oil quality, which is related to the oxidation, deposit formation, and allowed OCI length.

But the paper has ZERO mention of the CCS...but you claim that the BOQI and the paper prove each other in some sort of circular argument.

What do you think the CCS of a "thin" oil in the context of the paper and a Viscosity Index of 3 is going to indicate in terms of CCS ?

I don't see your point. Of course, the paper isn't mentioning my BOQI scheme, which uses the CCS viscosity, yes. That is something I put in relation to the paper.

This is the useful part with regard to the viscosity versus deposit formation:

"Evaporation is found to be highest for naphthenic and lowest for paraffinic. TGA results also show that overall the paraffinic neutrals have minimum volatility followed closely by PAO. The aromatics have much higher volatility than PAO, while naphthenic havethemaximumvolatilelossonheating. This is also supported from the low viscosity of naphthenic neutral andaromaticsat40and100°Candotherstudy[1].The oils with low viscosity tend to form relatively less deposit during oxidation. In both compound groups (ring and other paraffins including normal and iso-paraffins), evaporation, which is associated with oxidation processes, is found to increase with anincreasein VI ofthe oil, similar to TGANoack volatility. Except paraffinic neutrals (PN and HPN), all other samplesarestabletodepositformationtendencyat225°C.The insoluble deposit and volatile loss obtained from TFMO produced weak correlations with base oil structural parameters except average chain length (R2 of 0.72). Higher ACL of averagebaseoilstructureleadstolowerevaporation.Thismay be explained on the basis of increased viscosity due to longer alkyl chains. Kinematic viscosity at 100 °C was found to be a good predictor for % evaporation with R2 value of 0.94 (Fig. 5) and % deposit (R2 of 0.89). An increase in viscosity at 100 °C shows a decrease in the evaporation loss during oxidation of base oil. The oils with lower viscosity (at 100 °C) tend to form relatively less deposit during the oxidation. The TGA Noack volatility provides an R2 value of 0.65 for % evaporation and 0.64 for % insoluble deposits. Higher TGA Noackvolatility thus results in higherevaporationlossandlowerinsolubledeposits during oxidation of base oils."
 
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