Question: What is molybdenum’s real role?

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Wouldn't using the properly rated oil at the OEM specified interval would make this failure mode mostly non existent - or is that incorrect?

I am clueless mostly on engine oil chemistry so I am here to be educated. The premise of the OP is does Moly help with Friction wear / prolong engine life as that doesn't seem to be born out in real life examples, and the counter argument was that Friction is only 1 of 4 modes of wear.

Rare exceptions admitted, engine failures due to adhesive, fatigue or corrosive failure are functions of bad design or other root causes - like sticking EGR or lack of maintenance, not engine oil chemistry?

The premise of ILSAC 6B is to lower LSPI - so that's a possible oil failure mode correction for oil outside of friction but that's a fairly new thing for fairly specific engine types, so barring that - I haven't read or seen anything that would change my opinion.

However like I mentioned I am here to be educated, so am happy to change my mind.

If you're using the correct maintenance shedule.... severe duty where severe duty is due. Are you?

Engines start ageing from day 1. That's the last day they were in new condition. So at what day do they get worn enough to consider them damaged, or damaging the oil?

Anyway, Moly.... I would expect it to help with wear and against friction in the elastohydrodynamic lubrication regime, which you spend more time in when the oil is thinner vs a thicker oil.
 
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MoDTC, and some other liquid moly-based additives, also act as an anti-oxidant and LSPI quencher. Wear protection improves when combined with ZDDP. ZDDP tribofilms accelerate MoDTC absorption into MoS2 on the surface. You also get decomposition and sulfurization of moly-oxides with non-linear structures which boosts the tribofilm thickness. While MoDTC forms MoS2 at the surface, it does not pair well with MoS2 solid particles in the oil as MoS2 can impede the lubricity of the MoDTC tribofilm, resulting in a higher friction coefficient than if MoDTC is used alone. (aka MoS2 supplements do more harm than good when added to oils that contain MoDTC... however small that needle movement may be)
 
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I've asked this before a really long time ago (I think?), but is the sediment-like substance everyone keeps finding at the bottom of the Pz jugs MoS2 type moly falling out of suspension, while the MoDTC type moly found in M1 staying better in suspension?

Reason of my suspicion is that MoS2 added from the can as posted by many respected members here eventually settles onto the bottom of your engine's oil pan.
 

OVERKILL

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The data presented historically hasn't just been with regards to friction reduction, the same infineum paper showed wear reduction in sequence IVA for example:
Screen Shot 2022-05-13 at 11.19.10 AM.jpg


They also note that the combined durability of a ZDDP/MoDTC coating is much higher than either coating alone:
Screen Shot 2022-05-13 at 11.22.05 AM.jpg

Screen Shot 2022-05-13 at 11.22.41 AM.jpg


Of course somebody who worked for Infineum and literally wrote the book on high-performance functional fluids might know a thing or two about this subject:
Screen Shot 2022-09-04 at 10.24.35 PM.jpg


Which I expect is what you are hoping to get some input on, however, getting into proprietary formulation information is unlikely to happen here and Dave has already been excessively generous with the information he has chosen to share with us IMHO.

Ultimately, we have proof that moly reduces wear in addition to the universally agreed upon fact that it reduces friction. We also know that moly works synergistically with ZDDP to improve performance and surface coating durability. Moly is also complimentary, or can be complementary, depending on the overall formation, with other FM and AW additives like titanium, tungsten and even other types of moly (trimer + dimer for example).

No, you aren't going to see this reflected in cheap UOA's.
 

SubieRubyRoo

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The data presented historically hasn't just been with regards to friction reduction, the same infineum paper showed wear reduction in sequence IVA for example:
View attachment 128177

They also note that the combined durability of a ZDDP/MoDTC coating is much higher than either coating alone:
View attachment 128178
View attachment 128179

Of course somebody who worked for Infineum and literally wrote the book on high-performance functional fluids might know a thing or two about this subject:
View attachment 128182

Which I expect is what you are hoping to get some input on, however, getting into proprietary formulation information is unlikely to happen here and Dave has already been excessively generous with the information he has chosen to share with us IMHO.

Ultimately, we have proof that moly reduces wear in addition to the universally agreed upon fact that it reduces friction. We also know that moly works synergistically with ZDDP to improve performance and surface coating durability. Moly is also complimentary, or can be complementary, depending on the overall formation, with other FM and AW additives like titanium, tungsten and even other types of moly (trimer + dimer for example).

No, you aren't going to see this reflected in cheap UOA's.
Thanks Overkill. Yes, that’s some of what I’m looking for- I don’t care about proprietary formulations, just trying to understand what the mechanism is and how it works; it doesn’t make sense to me from personal and board UOAs that one can observe a factorial increase in moly content (there was a PP UOA not too long ago that was spiked with LG BioTech I believe) that went from say 48ppm moly to nearly 300ppm, and other than that element, the UOA looked like a carbon copy.

I get that there’s a reduction in friction, and that moly+ZDDP is extremely beneficial for protection, but the data side of me is asking “Where’s the beef?” If you will; what are the measurable benefits of di/tri moly adds to the average user, and do the benefits outweigh the cost of the special moly compounds?

I’m certainly not saying moly isn’t beneficial; are there any outward measurable characteristics of the benefits short of tearing down an engine and measuring the parts?

Also, it seems moly would be most beneficial in the ring pack area; Gokhan’s HTFS theory combined with the fact that moly is an EP friction reducer seems that at a minimum, not only should the moly keep the rings cleaner, but it should reduce bore wear and piston ring groove wear as well, correct?
 

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Dosage, competition at surfaces, all the complexities of the interactions, the forms of each component...

It is precise.

I will never ever use an additive again.
Agreed on no additives… I’m hoping maybe David can explain the whole moly process and what HPL sees as the benefits since measurable results seem to be in short supply at most of our UOA levels.
 

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...I’m certainly not saying moly isn’t beneficial; are there any outward measurable characteristics of the benefits short of tearing down an engine and measuring the parts?...
First, I think some viewers are confusing the MoS2 powders that are suspended in an oil carrier (from OTC and third party shelf-space takers) and MoDTC, which is a molybdenum atom combined with sulfur, oxygen, and carbon atoms to make a Molybdenum DiThioCarbamate (MoDTC) molecule, which is an oil soluble moly version. As explained above, MoDTC is very synergistic with ZDDP in that they aid each other when combined.


The MoDTC still forms sheets from the little platelets at the surface to reduce friction and in larger dosages, will form an even thicker set of platelets to act as an anti-wear additive, aiding ZDDP.

The only way to measure MoDTC's contribution is via friction modification tests and anti-wear tests (e,g. , the Plint reciprocating wear ring machine). Friction reduction may show up as a fraction of a percentage increase in mpg for tightly controlled mpg (fuel economy) tests.


Later research has shown that MoDTC, along with the addition of organic friction modifiers, result in another synergistic FM/AW combo in terms of further reducing friction and wear for low viscosity lubricants.
...Also, it seems moly would be most beneficial in the ring pack area; Gokhan’s HTFS theory combined with the fact that moly is an EP friction reducer seems that at a minimum, not only should the moly keep the rings cleaner, but it should reduce bore wear and piston ring groove wear as well, correct?
MoDTC should reduce wear and friction for any rubbing or reciprocating surface.
 
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there have been same engine type/ same owner samples that may show an oil with 2x/3x/5x for example more moly, yet the entire UOA can look essentially identical otherwise.
Suggests that more isn't (always) better (there's a point of diminishing returns).
 
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Suggests that more isn't (always) better (there's a point of diminishing returns).

Yes, its been shown that MoDTC + ZDDP combined values provide better results, than increasing MoDTC values alone.
 

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I have no specific knowledge of engines but I do have a good understanding of physics so please just see this as an inquiry more than a challenge. I'm really just looking for a more detailed explanation of your statements but let me start with my rationale.

I can't imagine there are ever two metal surfaces that come into close proximity to each other (close enough where the boundary layer is relevant) while moving anywhere in any engine regardless of the lubricant that doesn't have some non-zero friction coefficient.
The film thickness between moving parts changes due to load (N) and relative speed between the moving parts (Stribeck curve). In boundary lubrication. the asperities of the surfaces are contacting each other and causing wear.

1669598130755.png
 

OVERKILL

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Thanks Overkill. Yes, that’s some of what I’m looking for- I don’t care about proprietary formulations, just trying to understand what the mechanism is and how it works; it doesn’t make sense to me from personal and board UOAs that one can observe a factorial increase in moly content (there was a PP UOA not too long ago that was spiked with LG BioTech I believe) that went from say 48ppm moly to nearly 300ppm, and other than that element, the UOA looked like a carbon copy.
Because UOA's don't have the resolution to reproduce what say Infineum has seen in Sequence IVA. That's the short answer, lol.
I’m certainly not saying moly isn’t beneficial; are there any outward measurable characteristics of the benefits short of tearing down an engine and measuring the parts?
I mean, ultimately, tear-down testing is the proper mechanism to be used here ;)
Also, it seems moly would be most beneficial in the ring pack area; Gokhan’s HTFS theory combined with the fact that moly is an EP friction reducer seems that at a minimum, not only should the moly keep the rings cleaner, but it should reduce bore wear and piston ring groove wear as well, correct?
Moly does FM and AW, but I don't believe EP. This is why EP tests aren't run on engine oils, because EP properties aren't useful. Chlorinated products have incredible EP performance, but do bad, bad things in engine oils.
 

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Because UOA's don't have the resolution to reproduce what say Infineum has seen in Sequence IVA. That's the short answer, lol.

I mean, ultimately, tear-down testing is the proper mechanism to be used here ;)

Moly does FM and AW, but I don't believe EP. This is why EP tests aren't run on engine oils, because EP properties aren't useful. Chlorinated products have incredible EP performance, but do bad, bad things in engine oils.
Agree… so it seems to be reinforcing the point that moly is beneficial (never disputed), but doesn’t show up in any “consumer-grade testing” (also never disputed), but can reduce wear that can only be measured by a complete teardown, and is only relevant if the engine in question had been completely measured and recorded prior to initial assembly.

We all “know” trimer moly is a good additive, but if somebody came on the board making those claims for a new ‘wonder’ additive that could be proven with the same level of evidence as moly, we’d probably laugh it off as another snake oil…

It’s a tough pill to swallow that something is beneficial, but you’ll never actually “see” the benefits of it in real life, isn’t it? 😵‍💫
 

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Agree… so it seems to be reinforcing the point that moly is beneficial (never disputed), but doesn’t show up in any “consumer-grade testing” (also never disputed), but can reduce wear that can only be measured by a complete teardown, and is only relevant if the engine in question had been completely measured and recorded prior to initial assembly.

We all “know” trimer moly is a good additive, but if somebody came on the board making those claims for a new ‘wonder’ additive that could be proven with the same level of evidence as moly, we’d probably laugh it off as another snake oil…

It’s a tough pill to swallow that something is beneficial, but you’ll never actually “see” the benefits of it in real life, isn’t it? 😵‍💫
It's basically that most on BITOG lack the resources to perform the requisite testing and UOA's are not a valid proxy, no matter how much folks might want them to be.

I think when there's a technical paper from somebody like Infineum, it's compelling enough to cause those capable of critical thought to integrate that into their internal evaluation process or data library for further discussion/analysis. I really liked their trimer moly presentation, but it wasn't until talking it over with Dave at @High Performance Lubricants that I understood that trimer could also be complimentary with other FM's and that there was this wild, but totally variable, FM synergy that can take place.
 
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I have been on the road. I think Mola, Overkill and RDY4WAR have covered the majority of the topic. As far as the mechanism of the reported audible improvements, I’m not sure if it is completely relative to the moly concentration or if there are other factors. I have not personally experienced what Overkill has said but knowing his nature I don’t doubt what he is saying. We certainly do choose good materials overall. I’d be lying if I said I knew for sure which one or combination of more than one that have resulted in this kind of feedback. What I can say is that we spend a lot of time testing different combinations, looking for the best synergies while keeping everything well balanced. I would tend to believe it is a combination of a few things that is generating the positive results. I’m sorry that I don’t have a more direct answer.

David
 

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2. Do we really understand why moly appears to make an engine “softer” to the ear- is it because of the moly or the more-complete area that experiences hydrodynamic lubrication or…?

As said here frequently, causation is not correlation, especially when the results are so immeasurable as to be testing “noise”.
In order to really test the engine noise reduction hypothesis with and without moly, the engine would have to be instrumented with acoustic devices that span a wide frequency range, with acoustic devices both on and off the engine.

I have tested formulations with various moly versions and without moly and I couldn't tell (to my ears) if the engines (Nissan 4.0L and 3.5L) made more or less noise cold or hot.
 

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In order to really test the engine noise reduction hypothesis with and without moly, the engine would have to be instrumented with acoustic devices that span a wide frequency range.

I have tested formulations with and without various moly versions and I couldn't tell (to my ears) if the engines (Nissan 4.0 and 3.5L) made more or less noise cold or hot.
Thanks Mola. So the overall “takeaway” is: yes moly (trimers especially) is very slippery, and performs even better when blended with an appropriate dose of ZDDP; and, while wear is measurably reduced, one should never expect a visible difference on a consumer-grade UOA?
 

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Thanks Mola. So the overall “takeaway” is: yes moly (trimers especially) is very slippery, and performs even better when blended with an appropriate dose of ZDDP; and, while wear is measurably reduced, one should never expect a visible difference on a consumer-grade UOA?
That's about it! :)

As I mentioned before: The only way to measure MoDTC's contribution is via friction modification tests and anti-wear tests (e,g. , the Plint reciprocating wear ring machine). Friction reduction may show up as a fraction of a percentage increase in mpg for tightly controlled mpg (fuel economy) tests.
 
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