Before I replace the pump, there's one easy thing to try:

Does anyone know if the engine oil cooler thermostatic valve on the filter adapter (if stuck) can interrupt oil flow to the engine? If so, would it cause a loss of pressure (or increase) as measured on the gauge?

I can try disconnecting the cooler and/or remove the thermostatic valve and replace it with the original plug. I find it curious that some of the engines with coolers didn't have the thermostatic valve and wonder if dealers removed them for this very reason. <img src="/forums/images/graemlins/confused.gif" alt="" />

Frank