6of36
Spends too much time on here
Oil requirements, and oils have changed tremendously since the gas engine was invented. Until the 60s, straight 30 weight was the only oil recommended, except in extreme conditions. Cars had solid lifters in most cases. Oil was just oil. Since then, engines are manufactured differently, with different materials. Oils have been chemically altered, and now pretty much all use synthetic. If you look at the oil requirements on an engine from 10 years ago, the oil requirements were for a much lower spec of oil. I don't even know what the current spec is, but last time I payed attention to the bottle it was something like SG. Ten years ago, it was like SC. With better engineered synthetic oils, they can specify thinner oils, to get better mileage. I know two people who run the specified weight, and one has 270,000 miles, and the other 340,000 miles on their cars. They are both Ford vehicles, but that doesn't matter. The important thing is getting oil changes.
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