Molybedum in motor oil

You could be buying in to an "urban myth". Molybdenum (note the spelling) is a metallic extreme pressure lubricant but is not commonly used as an engine oil additive. The most common anti wear and extreme pressure wear additive is, get this, Zinc dialkyldithiophosphate and is used by every oil company in their motor oils as it is the best product for the job. Oils are categorized by an API (American petroleum institute) designation which outlines a minimum performance and durability requirement for any designation. Listed below are the various oil designations. An SG designated oil is superior to an SF designation, the higher the letter the higher the performance standard of any given oil. Since the letter designation represents a minimum given performance requirement it makes all oils of that designation equal. In other words to say Pennzoil is superior to Standard Chevron oil would be pure BS since both are rated equally in that same API designation. An oil can however exceed a designation in which case it usually states meets or exceeds API designation S* on the container. Also beware of oil additives as most are overpriced snake oil that are of little if any benefit over what a good quality motor oil changed at recommended intervals will provide. I see your name is Jim not Mark, however be my guest if you want to purchase them. Regards from a professional mechanic, Lugnut

Gasoline Engines: a.. SA - For engines operating under mild conditions. No special protection capabilities (mineral oil). b.. SB - For light-duty engine operation. Has anti-scuff capabilities, resists oil oxidation, retards bearing corrosion. c.. SC - Minimum requirements for all 1964 to 1967 passenger cars and light trucks. Controls high- and low-temperature deposits. Retards rust and corrosion in gasoline engines. d.. SD - For 1968 and later engine warranty service. Better high- and low-temperature deposit control than "SC". Also rust/corrosion resistant. e.. SE - For 1972 and later gasoline-engine warranty maintenance service. It provides maximum protection against rust, corrosion, wear, oil oxidation, and high-temperature deposits that can cause oil thickening. f.. SF - For gasoline engines in passenger cars and some trucks beginning with 1980 models operating under engine manufacturers' recommended maintenance procedures. g.. SG - This designation is for 1987 and newer car models. h.. SH - This designation is for 1994 and newer car models.

-- "They that can give up essential liberty to obtain a little temporary safety deserve neither liberty nor safety"

Benjamin Franklin

This is a case of "well it works in severe duty so it must be better than what we use for normal duty"

Molybedum based lubes operate on the "coating" principal in that the moly in the oil is supposed to coat the engine parts to make it run easier. The primary use of moly-oils is for boat engines, because a coating of moly is very good for preventing the formation of rust on steel. Boat engines sit for long periods near water without being run, so there's lots of opportunity for the oil to run completely off the inside of the engine and for water and oxygen to create rust.

Some people also claim that moly-coated bullets reduce fouling, and moly lubes are also used sometimes on guns used in dusty environments. The idea here is that the moly is deposited off onto the metal by the oil that is carrying it, and acts as a dry lube. (ie: the coating wears instead of the metal) Of course you got to keep applying it to keep the coating on the gun.

I've also read about people using it on old rear-axles to quiet them down, and in motorcycle engines where the transmission gears and engine share oil. However I never used moly-oil in my own motorcycle when I had it and I never had problems.

But in an auto engine I think that they really do nothing at all. In a properly running and properly lubed engine there is not supposed to be metal-to-metal contact on any wearing surfaces, because there's always supposed to be an oil film between metal surfaces. The only time there isn't an oil film is during startup, and a few other places (like piston rings) where there is extreme pressure. In short, the oil film "wears" not the metal surface, so a coating on the surface isn't doing anything.

Ted

What is this, a cut and paste of a ten year old technical article on motor oil? Zinc dialkyldithiophosphate hasn't been used in automotive motor oil since 1995 because it (zinc dialkyldithiophosphate) poisons catalytic convertors.

Current API motor oil designation for gasoline engines is SL.

Mobil's msds sheets still list it.

Interesting.

Lists ZDDP at 1.04%, anyone have a reference to what concentration of ZDDP was used in motor oil before OBD2 requirements?

metal-to-metal

Ted,

This site is where the net oil geeks hang out. Their opinion on moly does not appear to be consistent with your 'expert' analysis. What are your qualifications in regards to lubricants?

WHAT site are you talking about?

Since you fail to provide the site, perhaps you would care to reword their explanation here, for the rest of us non-omnipotent people who cannot read the URL out of your mind? Or are you not able to understand their explanation?

I don't see where you get off with this 'expert' bullshit anyway. Reread my explanation, I said that _I_believe_. Get a clue, dude. How much more clearer do I have to say something before morons like you understand that your reading an opinion, not a statement of fact?

Well I could say that I sell Amsoil that would qualify me for everything in lubricants, right? Although I don't see Molybedum in the Amsoil list of ingredients for their motor oil, (It's in their lithium grease, though) so I guess an Amsoil rep wouldn't agree with your net oil geeks either.

This is the Teflon thing all over again. People just can't seem to shake the idea that putting solids into motor oil (which displace the lubricating fluid) somehow improves lubrication in a garden variety car engine. You think Molybedum is so great, fine - post a link to a controlled study proving it's better in the average car engine. Until then you better accept that everything you read on it, regardless of who wrote it and how qualified they are, is nothing more than opinion only.

Ted

Sorry, here is the link. I did a search in the Virgin oil analysis section(VOA) to ascertain which lubricants contain Molybedum.

Caught redhanded, so the dodge is to beat on him for omitting the URL.

'believe' appears nowhere in your text. YOU get a clue.

non-sequiter

non-sequiter

You think

Now you're the one who needs to improve their reading comprehension. He started the thread with the post:

"Is this a good additive? A colleague indicated to buy motor oil with this ingredient in it. And Boron also. How do I find out what is in oil?"

Nowhere did he state he thought moly or boron were good components. Get off your high horse.

Until then you better accept that

Ted, you're great at backpedaling. You're also great at presenting an opinion as fact, then claiming later it was only an opinion.

Sheesh.

--Geoff

Well, I dug through the site searching on the term Molybdenum. (I assume that this is the same thing you meant, you just misspelled it, and no I'm not going to stoop to a spelling flame unlike some others in this forum)

Here's the most technical explanation of what it does I could find that someone posted (basically exactly what I said already - the coating principle):

"The moly in molybdenum trialkyldithocarbamate (MoTYDC's) starts out as a moly "pentasulfide" salt with a dithiocarbamate acid added. The salts are then stabilized with poly phenylene sulfide polymers and an alkyl group of

2-ethylheyl's. The result is a polymerized fluid that is slightly golden in color (light amber).

When in oil, the MoTDC decomposes to form "moly sulfide films on frictional surfaces, of which the particles adhered to the porous iron sulfide film produced by the reaction of the decomposed sulfur compounds and iron surfaces, and that these components make an extreme pressure or anti-wear film."

When used with ZDDP, a third layer of film is formed which creates an iron phosphide film. Stating it another way, three films are formed to create a plastic layer; MoS2, FePO4, and FeS. It is these three films that react under pressure to form a plastic "sliding" layer which prevents metal contact. I.E., instead of metals gouging into each other, they slide over one another on this "plastic" film."

Of course, the thing that the poster didn't explain is why in an engine would you have metals sliding over each other in the first place.

So, as I already said in my first post, in a properly running and properly lubed engine there is not supposed to be metal-to-metal contact on any wearing surfaces, (with few exceptions) because there's always supposed to be an oil film between metal surfaces

If you dig through the oil "geek site" for the thread the above came from (should be very easy) you will find as many people in that thread that claim Moly does nothing at all in a regular auto engine, as who claim that it does something.

There are several other "Moly" threads on the forums in that site, all as equally inconclusive over the benefits of it. A few people even pointed out that some engines disgorge Moly, see their used oil analysis section.

I'm going to file it in the "Synthetic Oil" pile - it's only better if you believe it's better! ;-)

Ted

Have nothing to say, so your going to metadiscuss. Well, OK then...

Initially that is true - he did not state that he thought they were good components in his first post. And if you bothered to read my followup I was not knocking Molybedum in all lubricants and all situations, only in the specific situation of an auto engine crankcase.

However his followup to me with the missing URL by it's context was clearly an attack on my opinion, with no supporting statements. In short, "Your wrong and I'm not going to explain why, just say that your wrong because a bunch of so-called Net Geeks on Oil believe differently" That is a pretty cowardly response, to not even put up a defence of why Moly in crankcase oil is a good thing, just say point blank that is is and anyone that thinks differently is wrong.

Frankly I don't care for that, and I react to things I don't care for. If someone is going to argue with me then at the very least they can present an explanation of why they think I'm wrong. He didn't, I came down on him. Maybe you are taking offence on the way I did - why? He didn't.

Geoff, I hate to break it to you but nobody gives a rip about your opinions of how I present anything. The people that are reading this thread are interested in the benefits/detriments of Moly. And so far you have contributed absolutely nothing of value to that discussion. I, by contrast, have. Even Jim has done more than you with his contribution of a most interesting URL. Perhaps you should learn from this.

Ted

Frankly, Ted, you must have, otherwise you wouldn't have seen fit to reply.

Nah. I'm satisfied that YOU'VE learned something. That's enough for me.

--Geoff

What, that your easy to flame?

Ted

No that you can rely upon your own high horse to be tripped up at every opportunity.

--Geoff

STILL nothing to contribute to the thread regarding Moly? Will you ever learn?

Ted

Ted, you haven't contributed anything to it in that vein in the past couple of days either. You're too busy nursing your wounded pride.

--Geoff