[jclark003]

Low oil pressure can be be serious and caused by several things including bearings, oil pump, pressure regulator, etc. engine should not be operated with OP below spec. Cummins typically has 2 sensors on their engines, one for OP gauge and a low pressure switch that triggers an alarm if pressure drops below 10 PSI. If gauge is showing low OP and alarm is going off then you likely have a problem and should have cummins take a look. Otherwise likely you have a bad sender. A little more information such as what pressure readings are you seeing at given rpm and whether alarm is sounding will be helpful. Otherwise first step is usually to install a mechanical presssure gauge or swap OP senders from other engine to verify that an actual problem exists.