So I just traded in my 2013 Ford Fusion Hybrid Titanium for a 2019 Ford Fusion Hybrid Titanium. I'm paranoid so I decide to swap the coolant from the Ford orange to the new yellow even though it's at 40,000 miles. I never removed the radiator drain plug/petcock; just loosened it and tightened it. When I checked it, the entire reservoir was empty. I tightened the petcock a bit, and then refilled with water just to see what was going on. It was empty this morning. Unfortunately, it's been raining so I can't really see where the leak is coming from. But do I just replace the drain plug, and where do I get it from? Thanks.