question is.. are you going by the factory gauge or going by the indicator light.. my suggestion would hook up a test gauge to verify your pressure. if the gauge shows a differant reading then I would say your wiring is at fault.
not familuar with the engine set up you have in your jeep....V6, Inline, if the sending unit is connected to a oil filter adapter plate.... had a Berratta GT that had the same problem.. changed sending unit, oil pump, crank, and it came down to the oil filter adapter plate had a gasket that had blown out and oil was by-passing when the engine got up to operating temp. changed the gasket and oil pressure went up to above normal ( installed high pressure pump ).