Modern Motor Oil Esters

[MolaKule]

Some people seem to want to further debate/discuss the following issue(s).

So the question is: Do modern Motor Oil Esters, such as described in (but not the only source of ester info)

http://theoildrop.server101.com/ubb/ultimatebb.php?ubb=get_topic;f=4;t=000056;p=1#000010

really posess a problem with

a. rust

b. hydrolysis

or

c. seal compatibility

in modern engine oils, hydraulic fluids, and gear lube formulations?


It would be advantageous if you presented chemical and tribological sources/data narrowly focused on the question above for your arguments.


[PS. This arose as a side issue from the following thread:

http://theoildrop.server101.com/cgi/ultimatebb.cgi?ubb=get_topic;f=1;t=007268

]

[ August 05, 2004, 02:52 PM: Message edited by: MolaKule ]

 

[MolaKule]

One could state (for example) the situation as such:

"Some people make the claim that modern ester formulations (such as Redline, etc) are detrimental to engines, gear lubes, and hydrualic oils, in the sense that they cause rusting through hydrolysis, and degrade seals. State from published literature, one source at a time per post, giving publication organization, date, and specific quote or passage that supports your argument."

Posting one reference per post gives the respondent a chance to review said claim(s) and time to respond.

 

[rgl]

If you take a look at the gun lubes part of the forum, there are a couple recent posts regarding Mobil 1 and ATF and corrosion prevention from personal tests.

Corrosion tests

Granted, this says nothing about an oil in an engine environment, but at least for pure corrosion protection Mobil 1 is not best, being beaten by regular ATF. However, I don't think there is much salt water inside an engine.

Furthermore, from personal use in firearms Mobil 1 does not itself cause any corrosion. None of this is remotely scientific, but it may be of help.

 

[buster]

Any significance to this corrosion comparison?

quote:

---

If to compare synthetic oils, according to tests run by our car magazine ester based oils showed considerably higher corrosivity then oils formulated mainly with PAO. To mesure weight loss of metal plates due to corrosion at 9.000 and 15.000 km it was used high temperature oxidation test (1 hour is considered as about 3.000 km). In the same table you will find shear stability. Unfortunately the procedure was not decribed: I could find only that they applied a higher temperature then 100 C (possible they used the same CEC L-14-A-93 with over 100 C and over 30 cycles).

...................................... Corrosion, g ........... Shear stability, %
Motul 300V 5W-30 ............. 7,0 ... 17,8 ............ - 9,0 ... - 3,0
Motul 8100 0W-40 ...................... 16,0 ....................... - 43,3
Shell Helix Ultra 0W-40 .................. 1,8 ....................... - 26,9
Mobil1 0W-40 ............................. 12,0 ...................... - 32,6
Castrol RS 0W-40 ......................... 7,0 ....................... - 49,5
Liqui Moly Synth. 5W-40 ................ 7,1 ....................... - 23,1
Chevron Delo-400 5W-40 ............. 10,0 ....................... - 40,0
Shell Helix Plus 10W-40 ....... 0,1 .... 8,2 .......... - 14,0 ... - 24,0
Castrol GTX5 10W-40 ......... 0,7 .... 3,3 .......... - 11,0 ... - 28,0
BP Visco 3000 10W-40 ........ 0,3 .... 6,0 ........... + 7,2 .... - 4,0
Valvoline Dura Blend ........... 3,7 ... 10,5 .......... - 25,0 ... - 27,0
Esso Ultra 10W-40 ............. 3,2 ... 11,0 .......... - 24,0 ... - 13,0
Castrol GTD 10W-40 ........... 2,0 .... 9,0 .......... - 10,0 ... - 29,0
Shell Helix Super 10W-40 .... 3,2 ... 12,0 .......... - 18,0 ... - 13,0
Liqui Moly Tour. 10W-40 ..... 5,6 ... 19,0 .......... + 12,0 ... + 41,0

---

[ August 05, 2004, 07:25 PM: Message edited by: buster ]

 

[Brian Reid]

quote:

---

MolaKule:
State from published literature, one source at a time per post, giving publication organization, date, and specific quote or passage that supports your argument."

Posting one reference per post gives the respondent a chance to review said claim(s) and time to respond.

---

Go ahead.

 

[Dan4510]

Hmmmmmmmmmmmm,

5614 posts v. 22....

Dan

 

[mf150]

not many peple willing to cite hardcore and specific evidence that ester is detrimental to the internal components of an engine.

this goes along with my personal experience that my engine runs even better on Red Line. I have no leakage, and my engine isn't rusting out from the inside...

i have to point out that the above personal sentiments are not scientifically based, so don't feel compelled to believe them.

 

[MolaKule]

Buster and Primus,

I recall in previous threads that there were serious questions regarding the validity of this table:

1. Test procedure and source of procedure. Was it ASTM tests or some ad hoc testing by a magazine?
2. metal types used
3. Many of these oils are group III, not PAO/ester formulations. For example, Valvoline Durablend, a blend of G1 and GIII mineral oils, or Chevron Delo shows almost as much corrosion as the ester blends, and therefore there is not enough differentiation to make this statisically significant. Many of these oils are foreign oils so it would be nice if it were assorted according to base groups for a better analysis.
4. If g is grams of metal, that's a "whole" lot of metal for a one hour corrosivity test. If in micrograms, it might have some validity. If it were the case for "grams" of corrosion, one would expect to see tens of thousands of ppm of ferrous and non-ferrous metals reported in a UOA. This has not been the case.

So I see no scientific validity for this table.

Again, I have yet to see any scientific or mechanical design periodicals (journals) making the case.

Even more interesting, I have yet to see any API publication making the case as well.

Addendum: I think now would be a good time for Mr. Reid to present some scientific data.

[ August 06, 2004, 12:25 AM: Message edited by: MolaKule ]

 

[theguru]

Motul have recently changed their formulation of 300v. One aspect that is supposed to be better is oxidation.

Isn't it easier to say "Motul" rather than "a supplier of Motocycle oil", if they are the same thing. They do seem to sell a large range of oils other than for motorcycles.

 

[Titanium_Alloy]

MoleKule,

I'd like to share my personal experience with Redline Power Steering Fluid. I'm sorry that this is not directly related to this thread since it was titled esters in motor oil (and not PSF).

Last year I did about 6 (or maybe 7) drain-refills of my PS system with Redline PS fluid to replace factory filled PSF. You can see results on Redline PS fluid posted in UOA section. Results weren't very good, but that's not the point of my story.

I was doing drain-refills with a plastic suction gun which has rubber part (about 1/2" thick) attached to the piston end (the one which goes into the cylinder) so it seals the cylinder well for a better vacuum. All drain-fills took about 2 maybe 3 weeks. After the 3rd drain fill I noticed that piston has difficulties fitting into a cylinder. By the 5 drain-fill I couldn't get the piston into the cylinder at all because the rubber part on the piston had swollen significantly. I had to get a new thing to finish last couple drain-fills. Some might say that all PS might do it. But this isn't what I noticed. Afterwards I did a multiple drain-fills on other 3 cars with a new suction gun and swelling didn't happen. I used it with Honda PSF, regular (SuperTech) and synthetic (Mobil 1) Dexron III, as well as with Valvoline SynPower PSF. NONE of the products exhibited ANY swelling (not even slight one, and certainly not to a degree of Redline PSF). This single observation convinced me against using Redline products. This was not a lab test, nor did I take any measurements, but I could clearly see actual problem due to severe rubber swell.

This might not be the case with motor oils (Redline in particular) or rubber types used in automotive industry.

MoleKule, it seems like you have access to a lab and you probably more experienced in lab experiments than most of us. It would be interesting to see the result of such simple experiment:
Take 2 or 3 (or more) equal-sized pieces of any (just for now) rubber and immerse them into motor oil, ATF, or PSF. I think that using Redline, Mobil 1, and maybe mineral Chevron or Castrol oils would be most appropriate.

After 24 hours at room temperature measure the rubber samples with micrometer to see if swelling or shrinking has occurred. If yes to what degree compared to initial measurements before the test. You might want to repeat measurements every 24 hours for a week to see if any additives prevent or even reverse swelling/shrinking.

Regards,

 

[rugerman1]

Titanium_Alloy ,
Bob did a similar test here: Does oil alone clean and condition seals???

Mark

 

[Brian Reid]

quote:

---

Titanium_Alloy:
,

After 24 hours at room temperature measure the rubber samples with micrometer to see if swelling or shrinking has occurred.

---

That's what I'd do if I wanted to check out a motor oil that I wanted to leave in my parked car over the weekend before I drained it.

Or you might leave a half dozen O ring seals in that many off-the-shelf motor oils for a couple of weeks or a month. Based on that, you'd pick the winners for further testing.

Field tests - extremes of hot and cold, contamination with a variety of substances, using large numbers of samples, under adverse and often unexpected conditions - separate the wolves from the sheep.

If you fail to do that, the public will do it for you. Dexcool is a recent notorious example of letting the public do the field tests.

 

[Brian Reid]

quote:

---

Dan4510:
Hmmmmmmmmmmmm,

5614 posts v. 22....

---

With a two-year head start.

And there's the old quality versus quantity issue.

 

[Brian Reid]

quote:

---

MolaKule:
I think now would be a good time for Mr. Reid to present some scientific data.

---

A good general picks the fight he can win. You'd like to have the beaker and theory battle.

This would be a good time for you to present the results of the field tests on a statistically valid sample of vehicles using a motor oil formulated with a Modern Motor Oil Ester base against a control of, say, Mobil 1 of the same viscosity.

 

[Brian Reid]

quote:

---

MolaKule:
So I see no scientific validity for this table.

Again, I have yet to see any scientific or mechanical design periodicals (journals) making the case.

---

Again, you aren't going to pay 1 dollar, or 1 cent, for the results of people taking your advice.

 

[Brian Reid]

quote:

---

guru:
Isn't it easier to say "Motul" rather than "a supplier of Motocycle oil", if they are the same thing.

---

Of course, if it's Maxima, it's not.

But mentioning Motul reminds me of something I've been hearing mentioned in a variety of contexts:

http://www.marketresearch.com/map/prod/701414.html

http://www.lubrizol.com/PressRoom/MediaCoverage/pdflibrary/chemmktreporter4_28_03.pdf

http://www2.exxonmobil.com/corporate/files/corporate/outlook_gtl.pdf

It's outside my area, but I understand that the Europeans don't have the manufacturing capacity in Group IIIs and IVs that North Americans have, and so use more esters (whether modern or not) in premium and super premium motor oils.

And, with the advent of the GF-4 specification, North American manufacturers are ramping up gas to liquid plants and closing down napthenic base manufacturing facilities.

 

[73Duster]

This information is from the May 1997 Plant Engineering magazine article titled Exclusion guide to synthetic lubricants. This has been republished again within the last few yrs.
Synthesized hydrocarbons, such as Polyalphaolefins and dialkylated benzenes, are the most common type. They provide performance characteristics closest to mineral oils and are compatible with them. They serve as engine and turbine oils, hydraulic fluids, gear and bearing circulating oils and compressor lubricants.
Organic esters, such as dibasic acid and polyol esters, easily accept additives, enhancing their applicability for finished product formulations, such as crankcase oils and compressor lubricates.
Note: crankcase does not mean combustion engine crankcase considering the source of the article.

Properties Polyalphaolefin Polyol Ester
Viscosity-temperature G G
Low-temperature G G
High-temperature oxidation VG E
stability
Compatibility w/mineral oil E F
Low volatility E E
Compatibility w/paints & E P
finishes
Hydrolytic stability E F
Antirust w/inhibitor E F
Additive solubility G VG
Seal swell performance E F

E=excellent; VG=very good; G=good; F=fair; P=poor

Hydrolytic adj, Hydrolysis n, a chemical reaction in which a substance reacts with water so as to be changed into one or more substances.

 

[Primus]

First, would I ask our moderators to delete my previous message since it was already posted by Buster ? TIA.

As for results themselves:

- the weight loss is in grams
- metal plates represent engine metallurgie (think similar to those used for Antifreeze testing)
- duration is 3 and 5 hours (not one hour)

Indeed, the authors have not indicated the test method, just specified it was "high temperature oxidation test". As I know it's quite usual test method to check properties in the lab. All magazines tests are made either in the lab of the Ministry of Defense or in the Moscow Research Insitute of Lubricants. We don't have private labs. I don't believe people working there are stupid to use something really unscientific and then to publish it. According to the magazine all oils were fully OK in respect of declared performance, but, as you understand, OK close to the high end and OK close to the low end of some property is not the same, otherwise it would sound like an average temperature of patients in the hospital. For us, readers, results may serve an indicator of some weaker sides that, at certain conditions, may be critical. By the way, these results are quite in line with those made in Australia and published by Exclusive Motosports, Melburn. The same weak points: oxidation, corrosion, chemical compatibility.

In addition, a few words about correct citing. Believe when saying about a higher corrosivity of esters vs PAO or mainly formulated with PAO, it was clear that this concerned PAO oils: 0W-40 from Shell, Mobil and Castrol, as well as conditionally considered as PAO: 5W-40 Liqui-Moly and Chevron Delo, but not all listed oils. And sorry, but I don't think 10 g with Chevron and 16-17 g with Motul are equal. May be in areas with mild climate where there is a high quality gas they will be equal, but given the bias I would bring some changes in oil intervals or change the brand itself.

 

[MolaKule]

quote:

---

MoleKule, it seems like you have access to a lab and you probably more experienced in lab experiments than most of us. It would be interesting to see the result of such simple experiment:
Take 2 or 3 (or more) equal-sized pieces of any (just for now) rubber and immerse them into motor oil, ATF, or PSF. I think that using Redline, Mobil 1, and maybe mineral Chevron or Castrol oils would be most appropriate.

After 24 hours at room temperature measure the rubber samples with micrometer to see if swelling or shrinking has occurred. If yes to what degree compared to initial measurements before the test. You might want to repeat measurements every 24 hours for a week to see if any additives prevent or even reverse swelling/shrinking.

---

Thanks Titanium, I'll acquire some Redline PS fluid and check it out. Just as a side note, for the last ten or 15 years, most PS fluids have been high ester content synthetic fluids.

Just for info, the only chemical or fluid (in the formulation industry) that I have seen that modifies seals to any great extent is a chemical family called the "cycloaliphatic hydrocarbons" and they mainly attacked axle seals. However, this family of fluids is NOT used in gear lubes.


BTW Titanium, check out the LC lab report. We did some similar elastomer tests for LC/FP using everything from plain rubber hoses to rear engine seals.

 

[MolaKule]

quote:

---

This would be a good time for you to present the results of the field tests on a statistically valid sample of vehicles using a motor oil formulated with a Modern Motor Oil Ester base against a control of, say, Mobil 1 of the same viscosity.

---

Mr Reid,

As I recall you raised the topic of API as the final authority on lubricating fluids, and you seemed to indicate that you had compelling research data to show this is true.

Please present your API information that shows that polyolesters or di-esters cause rusting and seal problems. You and the API should already have the data to support or invalidate the above proposition.

Surely, if the API won't approve polyolester or di-ester fluids because of baseoil/seal incompatibilities, they must have some compelling research data that you are privy to.


Mr Reid's profile indicates that he is an engineer, so I would expect him to also have access to labs and maybe some test data.


As a side note, Amsoil's 10W40 was API approved in 1974. It was a di-ester, TMP (polyolester) mix. Later of course, Amsoil switched over to PAO/ester mixes.

[Amsoil's XL7500 is a group III base oil, so one cannot point to it as a synthetic base oil having API approval. This was done so quick lube shops and their customers would feel comfortable with the API Starburts on the packaging].

[ August 06, 2004, 12:05 PM: Message edited by: MolaKule ]