re: 540RAT
I worked in an Oil lab of a large Oil Company. I did all the lab work for the engineers. It was a summer job...
I find the article below, unbecoming of an Engineer. If the guy disclosed his name. I am sure The Engineering Society will take his engineering ring back.
There is some truth in the article. For example, oil viscosity is not an indication of oil quality. It is just a spec that has to match the engine design....
Here is the stuff that is disturbing:
1. ASTM tests are valid, because they are standard repeatable tests. I and You can read the test description run the test and achieve the same result. Hence, we can compare results! and oils based on the tests!
2. ASTM tests tend to try to simulate or be similar to some real life conditions. Engineers have been using them to estimate real-life suitability of product. Based on the modern cars out there, I think, they have been doing OK.
3. BTW, common ASTM tests are at 80, 100 and 120C i.e. common oil operating temperature.
4. Once can invent the best most applicable test in the world. But this does not make it right or useful. If it cannot be replicated, what use is it. Just some nut case doing something in his garage? Remember, cold fusion?
Here are some simple truths:
1. Non-Synthetic oil varies widely in its composition. Every batch at the refinery is custom crafted to meet the spec based on the feed stock. So there is a lot of variability even for same blend. On the other hand, it is driven to same spec and has same additive package. For example, mix two similar base-stock or one very heavy and one very light to get the same viscosity (spec and index), the first will be very nice, the second will work but will have really bad behavior i.e. bad oil. The guy running the batch only has limited choices....
2. Synthetic has fewer different compounds and much nicer characteristics.
3. Pure oil is best for your engine in an ideal world...
4. Additives are necessary.
5. Wear improvers like Calcium, Zinc, Moly enhance wear characteristics. However, they are solids and plug up oil passages and leave residues. They also act as catalysts and acids in breaking the oil down. So, one has to be judicious in their use.
6. Race oils are designed to provide more protection at the cost of very frequent oil changes i.e. each race.
The main observations should be:
1. Buy synthetic from a reputable company.
2. Change it as often as you can afford.

3. Do not get hung up of additives, unless you are racing. Then change oil every 2 weeks or more.
4. There is no magic additive. PTFE was never designed to be put into oil or fuel. It is a Fluorinated compound. Florine radicals are nasty! Everything else is snake oil, unless the ingredients are disclosed.
5. The best that 'snake oil' additive can do is be just a small fancy bottle of 10W30 i.e. nothing.
ZDDP and Moly will find their way into the exhaust i.e. oil not scraped from cylinder walls, oil vapor not captured by the charcoal canister that gets re-cycled into the intake, etc. Only very small amounts are needed to poison the catalyst. This is why they are not used in modern oils.
Anton
Take a look at this site and the documentation this person put together. He has info on zddp as well. I found it all pretty enlightening. I posted this in the oil thread previously.
540RAT - Tech Facts, NOT Myths