That's just what my high school auto mechanics teacher told us and it stuck in my brain all these years. It's possible or likely that at that time he was talking about the powdered graphite. Certainly lubricant technology has changed over the years and even in the last 20 years. Rules of thumb that used to be gospel no longer apply.
The 3 month/3000 mile oil change interval is an example. I still go by the 3000 mile even though I know today's oil can easily last 5000 or more miles.
1950 Chevrolet 3100 (Ol' Roy)
1939 Packard Standard Eight Coupe (The Phantom) | 1956 Cadillac Coupe de Ville (The Bismarck) | 1964 Ford Galaxie 500 coupe |1966 Ford Mustang (Little Red) | 1969 Pontiac GTO (The Dishpit) I 1979 Ford F-100 | 1976 Ford F-150 (Big Red) | 1995 Ford F-150 (Newt)
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