Not saying there aren't "harsh" chemicals in motor oil (and it ain't like you're going to drink it), but I've never really heard of it in new oil-most of the time I hear that it's talking 'bout used oil, which I'm sure is full of some creepy stuff.
You can drive yourself nuts trying to outguess the makers-I'm sure all formulations change, but when I originally started running Mobil 1 in '76 one of the questions folks asked was how can you make it so thin? Mobil said because it would cling to metal and not tend to run back into the oil pan like conventional oils.
I have no idea what the 'best' is, but I've read a lot of oil stuff over the years by folks/companies that apparently intent on trying to knock Mobil 1 down a peg or two? I just stuck with it 'cuz it was
easy to find, and
pretty darn cheap compared to some of the boutique synthetics-kinda the same argument 'bout cheap gun oil (or Mobil 1) vs. the high priced spread?
I once tried a boutique motor oil in one of my bikes-the oil in Japanese bikes runs through both the transmission as well as the motor. At about 3,000 miles, you could feel the transmission shifts getting 'notchy'-a fresh load of boutique oil @ 5,000 miles and everything smooth again. I went back to Mobil 1 after that experiment, as I could not tell any difference in the transmission from the time I put it in until my normal 10,000 mile oil change. 'Course, the Mobil 1 was less than half the price of that boutique oil everybody raved about, and I could run it more than twice as long! :banghead:
I also had a relative that totaled an old Datsun with 180,000 miles on it. The mechanic that bought the car at salvage looked him up to find out what kind of oil he had been running in it-he said that was the cleanest looking engine he'd ever seen, 'specially with that many miles (and my relative also ran much more than 3,000 miles between oil changes).
Everybody seems to forget (or didn't know?) that when Mobil 1 came out it said 25,000 miles between oil changes-the original bottles had it in big red letters on the front/bottom label. My understanding is the reason they got away from making that claim was in order to not butt heads with the automakers, who still recommended oil changes @ 3,000 miles or so? (back around 1976).
Jest figuring-think my Weapon Shield comes out to around $1.38/oz. in a 16 oz bottle (splitting shipping with friends)-Mobil 1 comes out to around 14 cents/oz. or slightly cheaper (when on sale) buying in 5 qt. jugs at WalMart (most auto places in my area sell it in 4 qt. jugs).
I'm sure I'm not the only pragmatist in here looking at those figures and wondering izzat stuff really 10 times better than Mobil 1?