NAPA and O’Reilly’s carry GL-1 rated straight mineral oil which is what you want to use. I think (but may be wrong) any GL1 rated oil in 90 weight will work.

Looks like O’Reilly’s bought out Vast-Auto recently so you may have one around you.

Last edited by Phak1; 11/11/2024 10:31 PM. Reason: Additional info
Phil
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1952 Chevrolet 3100, Three on the Tree, 4:11 torque tube
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