Why would a 1997 V8 Aurora run SO HOT?

working on that myself. changed thermostat, (did get new coolant tank cap so now it does not boil over when the engine is turned off) sometimes a blown gasket is a contributor or culprit- they can test the coolant for exhaust fumes.. I have a minor gasket issue but not large enough to cause my overheat.. checking to see if the put in the wrong thermostat.. they had put in green antifreeze instead of Dexcoool... There is a air dam underneath the front of the car. It begins above the molding for the front bump and goes all the way past the top of the radiator. It screws into a brace about 3 inches above the lip of the bumper with 2 large push-pin type screws. If this air dam is damaged at all if will probably cause the car to overheat. Other than that, click on the a/c and see if your fans turn on, if they dont you probably have a dead fan or fan relay. This is more of a general rule of thumb for all cars.