I don't have the artical.
But a independent company with no affiliation to any Motor oil manufacture, tested every full synthetic oil on the market.
And almost every oil broke Down and stopped "Lubricating" at 2-3,000 miles. Penzoil was the worst at like 1500.
Valvoline was like 8000, Castrol about 5000. Mobil 1 full syn 25,000 miles before it STARTED to brake down.
I run it 10,000 and its still clean'ish when it comes out.
There "clean 5000" is better than most full syn oils
TLCA # 20314
84 Hilux, 22re Conversion, 63" chevy rears, Rears up front, Bobbed bed, duel e-lockers, 5.29's, 35" Ground Hogs
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