Looks like RP has improved since Calumet took them over.
Notice on the bottom they reference SWRI. Also notice how poor the shear stability is of the prior version of M1 EP. M1's formulation has changed since this test.
What I found interesting about their 5w30 HPS oil is it has a VI of 193 but is extremely shear stable per ASTM 6278.
"The oxidation resistance, synthetic solvency and varnish control contribute to incredible cleanliness inside the engine. These unique formulations enable HPS oils to outperform leading synthetic and conventional lubricants in both gasoline and diesel engines"
I guess they're using POE from Calumet if I had to guess being they are a manufacturer.
The XPR can clean as well.
Notice on the bottom they reference SWRI. Also notice how poor the shear stability is of the prior version of M1 EP. M1's formulation has changed since this test.
What I found interesting about their 5w30 HPS oil is it has a VI of 193 but is extremely shear stable per ASTM 6278.
"The oxidation resistance, synthetic solvency and varnish control contribute to incredible cleanliness inside the engine. These unique formulations enable HPS oils to outperform leading synthetic and conventional lubricants in both gasoline and diesel engines"
I guess they're using POE from Calumet if I had to guess being they are a manufacturer.
The XPR can clean as well.
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