I've used Bar's Stop Leak in a 2001 Windstar that had a blown head gasket and it completely stopped the leak. That's what I'd recommend, at least. Before using the stop leak, the oil looked like a milkshake. I changed the oil and kept monitoring it and so far the oil has stayed nice and clean and the coolant hasn't gone down. I think they've put about 5,000 miles on it since the "fix", and so far so good.