Cadillac Repair: 97 sts cadillac, engine threads, combustion chambers

Question
QUESTION: my car is overheating and i replaced the thermostat, waterpump, and radiator cap. it still overheats when i drive down the road not when idiling. theres water coming out my overflow and theres no water in my oil. please help me

ANSWER: What you have is the ever common fault of leaking head gaskets where the engine coolant is getting into the combustion chambers of the engine and the ONLY fix is to drill out the engine threads and install steel heli-coils in the engine block and replace the head gaskets and ALL the head bolts.

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QUESTION: ok and someone told me it could be the radiator do you think it could be that and whould it be better to change the motor or do your first response

Answer
If you have HIGH mileage on the vehicle, Over 100,000 miles I would replace the radiator with a NEW radiator, NOT a rebuilt one and replace the engine with a remanufactured engine that has the new head bolts installed. If you put in a junk yard engine you will over time have the same problem.