Our 50 year old Sunbeam had an incredible passenger door hinge squeak. Used the full gamut of penetrating oils and grease. Finally decided to try Liquid Wrench, a product that, years ago, I'd given up on as a penetrating oil. It stopped the squeak immediately and it has stayed stopped for over a year. Wife now complains the door will not stay open.
To be honest, this is the best performance I've experienced from any kind of "magic in a can" lubricant.
Bill