Last year at this time, I was driving along in the heat of the summer and all of a sudden my temperature gauge shot up to HOT. I immediately pulled over and saw the coolant leaking from near the water pump. It turned out to be a water outlet tube failure. The tube is a smaill plastic elbow that enters the engine block. It was a $15 part but about $ 150 more in labor. This year, almost exactly 1 year to the day, the same thing occurred. It was the second time in 2 years I had to repair the water outlet tube. Is this a known vulnerable part of the cooling system that causes many failures? Any ideas on how I can prevent these sudden, heat-related breakdowns? The car is a well-maintained 1998 Lumina LTZ 3.8L with 108,000 miles on it. No amount of preventive maintenance has helped me prevent the recurrence of this problem...