engine trouble, oil pressure diving

Before I put my car into storage the fall after I got it, I put a can of Rislone in it and put some miles on and then parked it in the warehouse for the winter. Next spring all was well driving it home from storage until I was about 1/2 mile from home and the oil light came on and the pressure gage took a dive. It seemed to recover but was much lower pressure than normal. Oil level was fine but it needed to be changed for the new season and to get rid of the Rislone crud. New Wix filter and oil and all was well. Pressure was back to normal if not higher than it had been, maybe due to fresh oil. Only thing I could come up with is that the Fram filter got clogged up with crud after the long soak Rislone treatment. I never thought to cut it open but I'm 99% sure that's what it was. The inside of the motor was squeaky clean, very little to no gunk/carbon left in the top end and the pan was very clean as well. So moral of the story is don't forget about the filter and use good ones. I'd suggest changing the filter and cut it open to see if you've got metal, check the drain pan too. You could have a bearing going away and an oil analysis will verify that if you can't read the drained oil. I used to use Blackstone Labs for my BMW M5 before I sold it.