Ok I don't think it's a rod. The car will run 100% to the driver if it was the rod "At the begining" But will start breaking and soon bust a whole in your block. But I would suggest going to your local auto parts and getting a bottle of Lucas. It's an oil that is kinda heavy and lubs the crap outta everything. If you still here the noise after you do this then chances are it's not your motor. Ummm I put 3 quarts of regular syntetic oil and one bottle of Lucas everytime I do an oil change. I burn less oil this way. Hope this helps.