Larry Crider
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Amsoil and aftermarket oil treatments containing Moly, ZDDP and other friction modifying-anti-wear type chemistry

I can’t tell you how many times I’ve had prospective customers ask me if adding aftermarket oil additives such as Lucas’ oil treatment, Liqui Moly MoS2, BG MOS or others is helpful.

So here goes………..I would not recommend adding 'Molybdenum Disulfide' (MoS2) [or any other aftermarket additive for that matter, including zinc] - which is the active ingredient in products such as "Liqui Moly MoS2 Anti-Friction Engine Treatment" - to our AMSOIL motor oils. Not only is it not needed, but it can actually have an adverse effect instead of adding extra protection.

Also…..Just on the off chance that someone would ever have an oil related warranty claim…..the first thing ANY oil company does (Including AMSOIL Inc) Is ask for a sample of the oil to ran through the lab….and when it come back with someone else’s chemistry in it….that’s right, You can forget about any warranty on the oil!

There are a few things I'd like to point out regarding the use of "Moly" in modern engine oils.

First of all, I should point out that "moly" (molybdenum) is one the most common anti-wear/friction modifier additive used in most modern motor oils - including AMSOIL's offerings - as well as in other lubricants, such as Greases.

Now what you need to understand is that in years past, the most common form of "moly" that was added to motor oil was in the form of Molybdenum Disulfide (MoS2). The problem with using this type of moly in motor oil formulations is that Molybdenum Disulfide is a solid and it has a bad habit of "falling out of suspension" in the oil.

However, most modern oil formulations today (including AMSOIL) no longer use this type of moly in their motor oils (although it is still commonly used in formulating greases). The common type of moly that is used in today’s oil formulations is "Molybdenum Dialkyldithiocarbamate" (MoDTC). This form of moly is 100% oil-soluble - which means that it remains suspended in the motor oil and does not fall out of suspension.

Molybdenum Dialkyldithiocarbamate (MoDTC) is an organo-molybdenum compound. The oil-soluble moly’s are considered to be organo-metallic friction reducers. They also provide very effective oxidation resistance.

I should also point out that Moly is just one of several different anti-wear or friction modifier additives that are used in modern motor oil formulations - others can include boron, ZDDP (zinc, phosphorus), titanium, etc. What truly matters in the end however, is the quality and performance of the finished blended product. The point is, motor oil can’t be judged solely by its base oils and individual additives – you need to take the entire formulation into account.

I should probably also point out that "moly" additives have a synergistic effect when used with other friction-modifier additives, such as ZDDP (zinc dialkyl dithiophosphate) for instance - the exchange between the dialkyldithiocarbamate portion and the dialkylthiophosphate in ZDDP influences the friction-modifying reaction of MoDTC. When used together MoDTC + ZDDP work much better than a high concentration of MoDTC alone.

Friction modification films consist of orderly, close-packed arrays of multimolecular "whiskers," loosely adhering to each other. The outer layers are sheared-off easily, allowing for low coefficient of friction. This phenomena can be described as a deck of plastic coated playing cards lying on the table and sliding off the top card easily.

Now as to how much moly AMSOIL uses in their motor oil formulations... What I can tell you is that they do use a good amount of Molybdenum Dialkyldithiocarbamate in their formulations (they have been for years).

I know that our older SS 0W-20 formulation for instance had somewhere between 140-150 ppm of moly in it - I believe that it's even higher in the new formulation.

Now there are several different flavors of MoDTC's. I have no idea which one AMSOIL is currently using in their motor oils as like all lubricant manufactures, they do not reveal there formulations -but they are most likely using more than one type - depending on the application. The exact formulation and moly treat rates will be highly dependent on its intended application.

One thing I can say though is that the type of moly used will be dependent on which additive company they are sourcing their additives from - there are only a small handful of them out there. For example, Infineum, which is co-owned by ExxonMobil and Shell, uses a "tri-nuclear" type of moly in their additive packages. Tri-nuclear moly happens to be a much more effective flavor of organic MoDTC that can be used in much lower concentrations than the more traditional types of moly. With treat rates of the trimer type of Mo FM, usually 70-100 ppm is all that is needed to get effective protection/friction modification.

When you see a VOA or UOA of a motor oil that has say 700+ ppm of moly in it, than you can be sure that that particular brand is not using "tri-nuclear" moly in their motor oil. I believe Idemitsu is one brand that is still using the older more traditional type of moly in their engine oils.

Now the fact that some oil brands, such as Idemitsu, advertise their use of moly in their motor oil - or that some their motor oils contain higher levels of it - does NOT mean that it is a superior product (any more than Castrol advertising that they use Titanium in some of their oils). Again, and I can't stress this enough, it's the quality and performance of the finished blended product that really matters.

Incidentally, the main reason that Mazda uses higher levels of Moly in their "factory fill" oils is to help protect internal engine components during break-in (it is debatable whether it actually does or not). After the engine is broken-in however, these higher levels of moly are no longer needed.

Oh and as to Idemitsu (or Mazda, or Toyota) branded motor oils being "superior" to AMSOIL's formulations... I can assure you that they are NOT (especially when compared to our Signature Series line). For one, they only contain Group III base oils in their blends (they don't use any base oils from Groups IV or V). Plus, their high Viscosity Indexes (VI) that are always "promoted" on many forums are due to the fact that they are loaded with Viscosity Modifier polymers (plastics), also know as Viscosity Index Improvers (VII).

So bottom line is, don’t waste your money!…..when buying a superior motor oil like Amsoil not only is there no need to add an aftermarket oil treatment but it is detrimental to do so as all you are doing altering Amsoil’s already advanced additive chemistry (and voiding or warranty to boot!)