If you can take the hinges apart, such as with a lift out stall divider, use a light application of grease. This would be also true with the spring loaded pins used in saddle racks, moveable tack walls and the like.

However, any grease applied to a regular door or window type of hinge will do little good. Because of its viscosity, it will generally stay on the surface and not penetrate into the pin and boss areas where it is needed the most. For these applications you need an lighter petroleum lubricant. Spray oils such as WD 40 and LPS are generally short lived when exposed to the weather. An automotive oil will provide longer lasting lubrication. I have been successfully using synthetic automatic transmission fluid, that stands up to our hot summers, and long winter storages.

A perfect applicator is a used syringe, which allows a pin point application, and eliminates any messy over lubrication.

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