I don’t blog or google much, but had to write something about the article in the current ML tilted “Choosing Between Synthetic Lubricants and Conventional Oils”. No author given …

It is surprising an article with so many technical errors and/or omission would be allowed in the class magazine. To name a few … It is stated that mineral oils are “aggressively solvent refined”. Some are, but most are hydrotreated API - Group II base oils that act much like synthetic oils (PAO’s). This really should be discussed in any fair comparison.

It also states that the specific molecular structure of synthetics keeps them from thinning – out under heat, which was somewhat surprising.

The discussion about shear strength and traction avoids the viscosity pressure issues surrounding naphthenic oils and paraffins as reported in the paper; “The effects of Pressure and Temperature on the Viscosity of lubricating Oils”, R.B. Dow, In the Journal of Applied physics, Vol.8 1937, pp 820-824. The relationship is too complex to discuss here and I’m not really qualified to begin with…

And at last I’ll stop with one more item …. The article was already spun in the title. Since when are Synthetic’s lubricants and conventional hydrocarbon’s simply oils?

Bill H.

I couldn't agree more. I read the article and found myself doing a lot of head shaking. Their info is usually accurate and unbiased. This article seemed to be very inaccurate and biased towards synthetics. Almost like the article never crossed the editors desk.

Hi Bill see you are still around, hows Douglas?
Bruce CLS

The choice between synthetic or mineral is based upon the machinery you used & ready to spend more as compared to mineral based.No doubt you will get better results than expected.

Hello, Bill.

quote:

Originally posted by Bill H.:
I don’t blog or google much, but had to write something about the article in the current ML tilted “Choosing Between Synthetic Lubricants and Conventional Oils”. No author given …

Easy to find article, with the data you are giving.

quote:

It is surprising an article with so many technical errors and/or omission would be allowed in the class magazine. To name a few … It is stated that mineral oils are “aggressively solvent refined”. Some are, but most are hydrotreated API - Group II base oils that act much like synthetic oils (PAO’s). This really should be discussed in any fair comparison.

I must disagree, Group II base oils are not like synthetic, you could wait that behaviour from a group III base oil and even so, PAOs are superior in performance in almost any application. There are a lot of comparisons and testimonials around.

quote:

It also states that the specific molecular structure of synthetics keeps them from thinning – out under heat, which was somewhat surprising.

We can see that in the viscosity index, it is not possible to avoid thinning, however, the molecular structure gives them higher resistance to face heat. Simple, they are almost pure compounds, they are not a complex mix, their properties are defined almost by design. On the other hand, the most severe hydrotreatment leaves a lot of molecules, may be not aromatics nor insaturated, but different molecular weights and size of the C´s backbone.

quote:

The discussion about shear strength and traction avoids the viscosity pressure issues surrounding naphthenic oils and paraffins as reported in the paper; “The effects of Pressure and Temperature on the Viscosity of lubricating Oils”, R.B. Dow, In the Journal of Applied physics, Vol.8 1937, pp 820-824. The relationship is too complex to discuss here and I’m not really qualified to begin with…

I have not read it yet, i will and i will post my comments , if any.

quote:

And at last I’ll stop with one more item …. The article was already spun in the title. Since when are Synthetic’s lubricants and conventional hydrocarbon’s simply oils?

Being english not my mother language i cannot see if there is a deeper meaning in these title, but for me is clear that, synthetic lubricant embraces as much as oils and greases, in the meantime, "conventional oils" makes me think in the same products after all, the lubroicant inngrases is oil. (lets forget for now MoS2 and C as graphite)

This post is very interesting, and i am eager to read replys to your statements and i hope replyes to mines too.

Best regards.