How do you replace the radiator in a 2003 Pontiac Montana?

To replace the radiator in a 2003 Pontiac Montana, first, ensure the engine is cool and disconnect the negative battery cable. Drain the coolant by removing the drain plug at the bottom of the radiator and detach the hoses connected to it. Remove the mounting bolts holding the radiator in place, lift it out, and install the new radiator by reversing the disassembly steps. Finally, refill the cooling system with the appropriate coolant and check for leaks.