A lubrication system for a plunger/packing set of a fluid end has a lubricating fluid reservoir, a pump cooperative with the lubricating fluid reservoir so as to pump a lubricating fluid from the lubricating fluid reservoir toward the plunger/packing set, a primary pressure transducer cooperative with the pump so as to measure a pressure of the lubricating fluid exiting the fluid pump, a secondary pressure transducer cooperative with the fluid end so as to measure a pressure of the lubricating fluid exiting the plunger/packing set, and a controller connected to the second pressure transducer so as to obtain a representation of the pressure measured by the secondary pressure transducer.