I'm confused by all of the interest in the Timken test relative to engine oils. It is primarily designed to measure the effect of chemical extreme pressure agents such as are used in gear oils. These "EP" agents have no function in an internal combustion engine.
You really have to go back to the basics of lubrication to get a better handle on what happens in an internal combustion engine. For any fluid to act as a lubricant, it must first be "polar" enough to wet the moving surfaces. Next, it must have a high resistance to surface boiling and vaporization at the temperatures encountered. Ideally the fluid should have "oiliness", which is difficult to measure but generally requires a rather large molecular structure. Even water can be a good lubricant under the right conditions.
Engine oils contain ZDDP (zinc-dithio-dialkyl-phosphate) additives for anti-wear (metal-to-metal rubbing) but no extreme pressure additives so of course they perform terribly in the Timken test (which, by the way, is quite poor in the area of repeatability and reproducibility). So I ask, other than for the purposes of snake oil salesmen, why all of this interest in the Timken test?