Controversial Moly

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Here's a short passage about molybdenum used as an additive in motor oils. It's from the blog for LNengineering:

Posted by lnengineering at 1:52 PM 0 comments

Thursday, December 6, 2007

Why "NOT" to use moly based engine...... - Tundra Solutions Forum

Why "NOT" to use moly based engine...... - Tundra Solutions

Forum: "Check out the OEM bulletin from Cummins. It is the Cummins Engine Oil Recommendations, Bulletin No. 3810340-02 . Its probably best if you stopped by a Cummins Dealer and purchased this bulletin- about $2 or $3.

On page 7 it has a section on FRICTION MODIFIERS states: 'There is firm evidence that certain friction modifiers, molybdenum dithiophosphate for example, can in certain formulations result in cam follower pin failure at relatively low mileage'........ From years working with engine test programs to approve engine oil formulations for API licensing, we can tell you that NO engine oil containing Molybdenum additives has been certified by the full range of engine tests necessary to gain API approval. Molybdenum compounds in motor oils can degrade and cause bearing corrosion and is particularly aggressive towards copper. In almost all cases, any engine oil formula having 'moly' will also contain a Copper Deactivator which will protect bearings from the moly compounds. The only problem, the copper deactivator decomposes at relatively low temperatures and looses it's potency after a few thousand miles."

Bob Cousimano over at CMW Oil also is a firm believe that soluble moly products should not be used in automotive lubricants, just like PTFE (teflon) and many other oil additive products like Prolong, Slick 50, and countless others just plain don't work and should never be used in an engine.
 
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Originally Posted By: Built_Well
... we can tell you that NO engine oil containing Molybdenum additives has been certified by the full range of engine tests necessary to gain API approval. ...



Do I not know what I'm talking about or is that statement easily provably false? Plenty of API SM oils seem to have moly in them...
 
I think that paper is dated!!! Most oils includeing a lot of fleet 15W40's have some moly in them! I also think that the various forms of man made moly are significantly different then how it is found in nature in it's rock form!The moly used in motor oil is drasticly different then what is normaly used in grease's!Almost all of your API certified SM oils have moly in them especialy 5W20's!Then you have the factory oils like Honda's break in oil that has more moly the Redline or at least close to it!!LOL
 
John is correct, that paper is very dated. Before soluble moly, people were pouring in all kinds of additives to their oil, and some of them were non-soluble moly, graphite, etc. This is the moly that Cummins was talking about. Somewhere Schaeffer's has a letter talking about this.
 
I don!t think Honda would use it in their factory fill if it was bad. There was negative talk about parrafin based oils, recently I read an article that said parrafin based oils are better. I have seen comments by people in the industry in the past that questioned whether 5w-20 would affect the longevity of engines. Now you see that it has better add packs than 5w-30 and other comments. It!s tough to know what to believe sometimes.
 
Originally Posted By: Built_Well
... we can tell you that NO engine oil containing Molybdenum additives has been certified by the full range of engine tests necessary to gain API approval.

Uh...No.

Mobil 1 5w-30 = API SM & CF, ACEA A1, ILSAC GF-4; approx 80~90 ppm moly

Mobil 1 0W-40 = API SM & CF, ACEA A3, ILSAC GF-4; approx 70~80 ppm moly

Castrol Syntec 5W-30 = API SM & CF, ACEA A1, ILSAC GF-4; approx 100~110 ppm moly

BMW Synthetic 5W-30 = ACEA A3; approx 110~130 ppm moly

On the flip side though -
Most Redline oils in at least the XW-30 to XW-40 range are heavily doped with moly, in excess of 500 ppm (and in one UOA as high as 1100 ppm). None of these oils are API or ACEA approved.

The Motul 300V series is also moly heavy at over 700 ppm in the 5W-30 and 5W-40. These are also not API or ACEA approved.
 
Originally Posted By: Tempest
Total excrement.


You mean my Harley or the paper?
grin2.gif
 
Originally Posted By: Michelob
I don!t think Honda would use it in their factory fill if it was bad.


My UOA of the Toyota factory fill in my Tundra also showed a healthy dose of Moly.

One can argue if this moly was in the oil when it was added to the new and empty engine or if its from assembly lube. But for sure, there was moly in it when it came out of the engine...

later,
b
 
uhh, I think "Molybdenum compounds in motor oils can degrade and cause bearing corrosion and is particularly aggressive towards copper." is mistaken. MoS2 is a Moly-sulphur compound. Sulphur is well known for attacking yellow metals. I believe this guy is unaware of non-sulphuric moly compounds, and is falsely condemning, literally all moly compounds.
 
This paper makes about as much sense as the "Using regular Pennzoil chokes all engines with sludge" stories.

As it has been stated before, all kinds of oils contain it, and somehow they pass metal compatibility tests.
 
Quote:
Bob Cousimano over at CMW Oil also is a firm believe that soluble moly products should not be used in automotive lubricants, just like PTFE (teflon) and many other oil additive products like Prolong, Slick 50, and countless others just plain don't work and should never be used in an engine.


Indeed, this is an old report, comes up occasionlly, and has been discussed at least three times before. To compare soluble moly to the snake oil additives is ludicrous.

The fact is, a specific and early compound of moly, a class of molybdenum phosphordithioates, was "suspected" as being the cause of some corrosion. There was never a proven correlation.

Interestingly, those same molybdenum phosphordithioates have been used successfully in hydraulic oils without any problems or suspected corrosion problems.

Today's modern molybdenum dithiocarbamates, have never been the center of controversy or suspected corrosion.

In addition, the comment about the copper deactivator is also out of date and no longer correct.
 
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