There is a Mechanical Engineer who did a “extreme pressure wear test” of 212 different off-the-shelf oils and some oils+additives. He wrote a very, Very, VERY detailed blog on it and posted all of his findings by rankings. Now his basis for the testing is designed more around the old flat tappet cam push rod American V8, which does and does not coincide with more modern engines. His testing method is quite extreme but does not (as he admits) specifically duplicate the pressures associated inside of an internal combustion engine. He attempts to duplicate the oil film coating associated with the traditional mechanical flat tappet cam against cam lobes for his tests. His test method specifically targets an oil’s resistance to wear at operating temperature through the oil’s break-down temperature in a 30 second test, then measuring the “scarring” or spalling of the test materials. Does this apply specifically to our engines (specifically the 5.4/4.6 family)? Yes and no. Yes we do have oil film contact surfaces in our engines. But, we do not have the extreme point to point contact associated with the flat tappet cam. Take that for what you will. He also touches on Used Oil Analysis, but in his opinion a UOA is “closing the barn door after the horse is out” and a waste of money (of which I STRONGLY disagree). The UOA provides an excellent look at the internal health of an engine. To me the UOA is not about the actual oil but more about the engine components and their current status, which coupled with a history of UOAs can help alleviate premature wear and failure and even help predict possible future issues.
The blog is several hundred pages and I am still reviewing it but the synopsis is that HIGH Zinc/Phosphate oils are not as ‘wear resistant’ as advertised. His science is true; physics don’t lie. He also proves (through scientific method and aerospace testing methodology) that a majority of oil additives actual REDUCE the effectiveness of oil under pressures at operating temperature (212-278* F with oil preheated to 250* for testing).
He is correct on the main point: too much zinc/phosphate IS actually bad for an engine. Zinc and phosphate actually attack the metals of the engine, specifically iron. But this point has been known for years, especially to the “newer generation” of engine builders. The older generation tend to stick to the “we’ve always done it this way” methodology, hence the “tried and true” ultra high-zinc break-in oils and products marketed ad-nauseam.
What is not addressed is the differences of the oil applications (ie: different engine types) as his basis for his testing is specifically for the Big Block Chevy V8. Aluminum engines and components respond differently than iron. Roller cam, roller rockers, hydraulic buffering lifters/buckets, bee hive/dual valve springs, hydraulic adjustable pushrods all were developed to reduce this specific friction point. The entire study needs to be looked at with an open mind and an educational/observational point of view.
Now, I personally have not looked into the Archoil product, and I don’t believe ANY hype and/or so-called testimonials. As far as I am concerned advertising and testimonials fall into the” Its all ******** and its all bad for you “ category.
I will link the blog shortly as its on the laptop and not my phone (which gets 99% of my r&d duty).