5W20 Group III and Moly

[MolaKule]

JTC's comments and web site referral reminded me of a paper I read recently that showed a formulated oil that had a number of good characteristics.

The formualtion was a 5W20 Group III base oil with a Moly additive package.

Paper stated that this may be the only way to produce a low-cost [relative term, mind you] oil formulation for the low viscosity, high mileage oils rewquired by many new engine manufacturers for warranty and for CAFE puposes.

 

[Patman]

If I owned a new car that called for 5w20, the only way I'd run that viscosity oil would be if that oil had moly in it. I just think that thin 20 wt would shear back too easily with hard driving. Otherwise I'd just use a 10w30.

 

[MolaKule]

Just reporting the paper.

Personally, I would fear there would not be enough hydrodynamic lubrication for this thin an oil film and the fluid would be depending a lot on the boundary additive, in this case, Moly.

 

[jason07-1zzfe]

If it is relying so much on boundry lube, doesn't that kind of defeat the purpose of using 5w20 (fuel economy), since AW and FM lubrication has much higher friction than full hydrodynamic?

 

[MolaKule]

Excellent point.

I think what they are try to do is beat the stats and hope that lubrication stays in the hydrodynamic state while hoping that lower viscosites will reduce vicous friction losses.

 

[Jay]

quote:

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Originally posted by MolaKule:
JTC's comments and web site referral reminded me of a paper I read recently that showed a formulated oil that had a number of good characteristics.

The formualtion was a 5W20 Group III base oil with a Moly additive package.

Paper stated that this may be the only way to produce a low-cost [relative term, mind you] oil formulation for the low viscosity, high mileage oils rewquired by many new engine manufacturers for warranty and for CAFE puposes.

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Molakule, was this oil Mobil Drive Clean 5w-20? The reason I ask is that I just called Mobil and asked what the basestocks were in Drive Clean 5w-20 and he told me all group III.

I'm fairly certain that the factory-fill break-in oil for my '02 RSX was Mobil Drive Clean 5w-20 with a dollop of moly. I was very pleased with the oil. It gave me good gas mileage, my consumption was extremely low and an oil analysis at 5,000mi showed that the oil held up very well. I can't say much about wear performance because it was break-in oil.

This oil had to pass a double-length sequence IIIF test to gain Honda and Ford's approval so the group III basestocks make sense for this grade. This oil sells for $1.80 at the WalMart in my area. It's a great bargain compared to AMSOIL's pricy 5w-20 with the same basestocks.

 

[MolaKule]

Jay,

No, this wasn't Mobil; this technical paper was from a foreign source as I recall. Off the top of my head I think it was from some Romanian researchers. It was interesting and sounded like a logical approach, but not very convincing, testwise.