What tests by whom? Just wondering.
Engineer's blog
1. 5W30 Quaker State “Full Synthetic” (abbreviated QSFS), dexos 1 Gen 2, ILSAC GF-6A, API SP = 152,674 psi
And that psi value sets a WHOPPING NEW ALL-TIME RECORD for motor oils that I have put through my Engineering Torture Test on motor oil. It was tested in Spring 2021.
This new 5W30 Quaker State “Full Synthetic” motor oil replaces the previous 5W30 Quaker State “Ultimate Durability” (abbreviated QSUD) synthetic.
zinc = TBD
phos = TBD
moly = TBD
The psi value of this new oil, which came from testing it at the normal operating test temperature of 230*F, put it in the SPECTACULAR 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. But, even at that elevated temperature, this oil produced an extremely impressive 148,133 psi, which was only a small 3% drop in capability. And that value put this much hotter and thinner oil in the AMAZING Wear Protection Category.
I also tested this oil to find out its onset of thermal breakdown, which was 290*F.
This new oil was purchased at Walmart. And its truly amazing performance is further proof that Walmart is selling legitimate motor oil, even though their prices are extremely low compared to typical Auto Parts Stores.
Many of us who have been devoted users of the previous Quaker State “Ultimate Durability” motor oil, were concerned that Quaker State’s Corporate bean counters might get their hands on this new Quaker State “Full Synthetic” oil, and cut costs that would ruin the oil. Fortunately, as it turned out, that did not happen. And in fact, now this latest new 5W30 Quaker State “Full Synthetic” motor oil, is BY FAR, the BEST PERFORMING motor oil that I have ever tested. This is absolute proof that Quaker State REALLY knows how to formulate motor oil.