Here are 2 of the high temp compatible oils he has tested. He recommends an oil with a higher top number than a 30 for air-cooled motors but it's hard to argue with a wear test. Only true test is your hot oil pressure reading at idle.
2. 5W30 Tribodyn, synthetic = 135,434 psi
This oil has no API certifications, but the bottle claims that the oil meets the API SN specs. The bottle also says do NOT use this as break-in oil, and also that this oil is NOT recommended for wet clutch applications. It also cautions to shake the bottle well before use. NOTE: I always thoroughly shake every bottle of oil before performing my Engineering Torture Test on it. This oil is made in the U.S.A, and was tested summer 2020.
zinc = TBD
phos = TBD
moly = TBD
The psi value of this oil, which came from testing it at the normal operating test temperature of 230*F, put it in the FANTASTIC Wear Protection Category. However, I went on to also test this oil at the much higher temperature of 275*F. At that elevated temperature, most hotter and thinner oils typically experience a drop in Wear Protection Capability. However, this is one of those rare motor oils that produced an increase in its wear protection capability at higher temperature. It produced 143,801 psi at 275*F, which was up 6% from its 230*F value. And even at that elevated temperature, this much hotter and thinner oil was of course still in the FANTASTIC Wear Protection Category. I also tested this oil to find out its onset of thermal breakdown, which was 280*F.
At the time of this writing, I had tested 240 motor oils. And this oil produced the highest wear protection psi values I have ever seen from a motor oil just as it comes, right out of the bottle. Very impressive for an oil that few people have even heard of. However, it fell wildly short of the wear protection capability that this maker claimed it produced in a European University wear protection capability test. In that test, they claimed 5W30 Tribodyn street oil produced 54 times, yes 54 times as much psi as 0W40 Amsoil Signature Series oil. Of course a claim like that is totally absurd, and insults our intelligence. As you can see just below, Amsoil Signature Series oils were the highest ranked oils of all the oils I had tested, until I did this test on 5W30 Tribodyn synthetic oil. And the Tribodyn actually produced only slightly better psi numbers than Amsoil. Buyer beware of blatant false advertising.
6. 5W30 Quaker State Ultimate Durability, dexos 1 – Gen 2, API SN “Plus”, synthetic (green bottle) = 133,125 psi
This oil was tested again in late 2019 for two reasons:
1. It became available with the API SN “Plus” certification, so there was an interest in seeing if there were any changes in its performance.
2. This oil was purchased at Walmart. And that was significant because it was so shockingly cheap at Walmart, compared to mainstream Auto Parts Stores, that there were concerns that Walmart might be selling counterfeit oil. Here’s why:
This oil was purchased at Walmart in late 2019, where the price was about $6.00 per quart bottle, and about $20.00 per 5 quart jug. At the same time, a few miles away, this oil’s price at Pep Boys Auto Parts Store was about $9.00 per quart, and about $35.00 per 5 quart jug. So, there was a need to find out if this oil being sold so cheap at Walmart was legitimate or not. Sure, you could say that Walmart makes such large purchases that it gets a break on price. But then, you could say the same thing about Pep Boys Auto Parts chain stores. But, the proof was in the pudding as they say. And as you can see by the psi value and ranking position above, this is the best performing 5W30 Quaker State Ultimate Durability, that I’ve ever tested. So, Walmart gets a clean bill of health. They are selling legitimate QSUD, and there is nothing to be concerned about. Now, we would have a hard time justifying buying this oil anywhere besides Walmart.
zinc = TBD
phos = TBD
moly = TBD
The psi value of this oil, which came from testing it at the normal operating test temperature of 230*F, put it in the FANTASTIC Wear Protection Category.
However, I went on to also test this oil at the much higher temperature of 275*F. At that elevated temperature, any hotter and thinner oil is expected to experience a drop in Wear Protection Capability. And this oil did have a 13% drop in capability. However, even at that reduced value down to 115,764 psi, this much hotter and thinner oil was in the INCREDIBLE Wear Protection Category.
I also tested this oil to find out its onset of thermal breakdown, which was 275*F