This is strictly rumour but I'm sure lots of you heard it over the years.
What ingredient in the original GM Positraction oil forced GM to change the formula because of it being banned or at least considered politically incorrect to use?
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1966 Strato Chief 2 door, 427 4 speed, 45,000 original miles
1966 Grande Parisienne, 396 1 of 23 factory air cars