Chevrolet Repair Questions? Ask a Mechanic for Answers ASAP
Hi, I am Mike, welcome. I'm reviewing your question.
Remove the oil pressure sensor and screw in a oil pressure hand held tester into that hole and check the real oil pressure. If it's ok, then the problem is with the sensor and/or wiring. If the oil pressure is really low, I would not run that engine anymore until you find out what is the problem. Make sure you don't have 2 gaskets on the engine oil filter. I don't know even if that leaked if that would cause low oil pressure but I have seen people miss that the gasket or o-ring had stuck to the block surface when removing the oil filer, than they put on a new gasket/o-ring and it ends up having 2 gaskets/O-rings and it leaks.
Other than that you may have to drop the pan again and check the pickup tube for being loose. I doubt if the oil pump took a dump on you that quick.