I have a story. Ordered 65 Mustang brand new, Aug, 1964. 5 weeks delivery, ordered High Performance Package, 289-271 HP, solid lifters, forged pistons, up-graded rings. Ran with Texaco Havoline 10W-30 for quite a long time, then Mobil 1 Synthetic came out, so I tried it. Car had crossed entire U.S. several times by then, even with 3.89 gears, engine "singing" on new interstates, never used measurable amount of oil between 3000 mile changes. Lo and behold, after 1000 miles on Mobil 1, it was down A QUART! Dumped it, returned to Havoline, ran as before.
Never tried the **** again! To boot, back then, it cost at least 10 times as much as good old Texas Naphthenic base Havoline. Pennsylvania crude, called "paraffinic", and touted as THE BEST, is in my m ind of lesser value from a lubricity standpoint than naphthenic. Naphtha is, of course, Benzine, which greatly resembles gasoline, and is derived from the crude. We all know Paraffin is WAX.
I have never used any Penn. based motor oil, the great quality notwithstanding. No doubt, today's synthetics are greatly improved; I am still an old die-hard S.O.B. Got that way learning harsh lessons of reality!
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