I have 99 cadillac sls with 105k miles on it. The radiator,cap,thermostat has been replaced brand new earlier this year. Since then it's been fine, but now its overheating with full 50/50 coolant in it. It then starts to leak coolant on passenger side front end of engine when it started to overheat. I turned the car off but the computer takes over making the engine run idle and radiator fans on. I am curious to if it's a external/internal leak, water pump , thermostat,hose, or cap. No head gasket has been blown yet no visible or audible damage. Besides the leak underneath as stated above.