The rough running indicates a possibility of head gasket failure as you could be loosing compression in one or more cylinders resulting in misfiring.
Get a compression test done to confirm.
If the oil leak was not there previously, the overheating has caused it and you need to check if it is from the cylinder head.
A bad head gasket does not necessarily mean coolant would get to the engine oil, at least not yet if problem is still new.
Sunday, June 3rd, 2012 AT 7:41 AM