I just changed the radiator n thermostat on my 03 g35 n still overheats
Theres much more to the cooling system than that. As its an 03, I would assume its due (or overdue) for a water pump. The engine coolant temp sensor may be faulty and not turning the fans on, or giving a false reading at the gauge. Your head gaskets or intake gasket could be bad. And after changing the radiator and t-stat, air is in the cooling system. If not purged, the air will cause overheating. Keep digging, look for leaks. If you dont find the issue, let a shop do a radiator pressure test and a leakdown test.
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