I had a similar problem, 116K on the original, just steamed a litte every now and then, more noticeable on cold humid days below 30. Even with the leak, never runs hot or overheats. When cold, there's no leak, even with a pressure test at a service station. This went on for months. The plastic metal ones do this when they get old. The mechanic said to leave it and wait until warm weather, but I had some extra cash and decided to replace it with a new all metal one. It cost under $200 for the radiator alone but since was too cold out, I paid to have it installed: $370 total job at a local service station, no more leak and piece of mind for the summer when it hits 98 out! Plus the aftermarket on is all black, looks cool through the grill!
