My Dodge Magnum 2005 was overheating and I change my thermostat on my Dodge Magn

Most likely cause if no visible signs of coolant leaks would be the water pump. Thermostats are simple parts that are most often prematurely changed. Check your water pump seep hole for signs of corrosion indicating a leak. Im not sure of your engine type but if the thermostat was located behind the alternator and the air conditioning pump then the seep hole will be right below the thermostat. with a bright light you can see it from under the vehicle but its not easy to locate. Hope this helps :)