Started out with a small coolant leak. Figured I had a little while to change it. My upper radiator hose had a small crack in it which is normal so I changed it. I think it was about 15 or 20 bucks at autozone. But the leak continued. The leak was getting bigger and bigger. I was going through a gallon of Dex Cool coolant every other day. The coolant is about 10 to 12 dollars a gallon depending where you buy it. I found the leak. There was a long crack down the left side of my radiator. The sides of the radiator are plastic so that problems like this will happen so you will have to buy a radiator for a little less than 300 bucks at autozone. (Thats the cheap one!!) So I replaced the radiator. Then I was driving one day and happened to notice that my car was getting hot. I had to have someone bring me some coolant and I barely made it home. It was my thermostat this time. The thermostat is about 13 bucks at autozone. Then about a week later I changed my oil and noticed yet another coolant leak. This time it was my water pump. I found the water pump on ebay, which can save you alot of money on car parts, for about 40 bucks after shipping. They are like $61 at autozone. I had it changed. The 500 bucks I had listed was just for parts and it is probably a little shy of the real number. My buddy works on my caddy for a third of the price of mechanic shops so I have saved a lot of money that way but I have probably paid him at least a couple hundred dollars in labor just on my cooling system. So the moral of the story is Cadillac Coolant systems Suck and I'm sure this isn't the end of my problems!