I have a 2002 Chrysler pt cruiser with 97,000 miles. When I stop the vehicle, the oil lamp comes on. When I'm driving, the lamp is off. It doesn't come on all the time when stopped either. The oil level is fine when checked after I let it rest about 5 minutes. Also, the engine at highway speeds (70 or so) sounds a lot louder than it should. It's a mix of a very high "screaming" sound with a very low but loud hum. No ticking problems. The engine mounts are a bit worn, so I didn't know if that would contribute to it. Anyone have any suggestions? Should I get an oil change now (due in 1,000 miles) and go from 5w-30 to 10w-30? Thanks for the help!