I have a problem when my 2015 Ram Cummins Truck reaches half tank fuel the delivery of fuel to the engine becomes sporadic sometimes the engine dies at 1/4 to 3/8 tank sometimes while I'm driving the fuel rail pressure drops to 1-2k and that's bad what is causing this? the pump in the tank? pump CP3? or filters? I have changed at 5 and 3 thousand miles front and back filters. truck runs so smooth with zero vibration when tank is full to half full. Help help help I'm the guy that gets 25-33 MPGs freeway.