I have an '86 535i, and recently, my oil pan was cracked and I lost all my oil. Unfortantely, I drove for about 100 miles (of hard driving) with no oil before I realized the pan was cracked. I replaced the pan and gasket and refilled with oil, and now I have a grinding type sound (like metal scraping on metal) coming from the engine just around 1800 rpm. Any ideas on what this is or how to fix it or if it's serious? Or if they're even related?