How do you flush radiator on a 2003 international 4300?

To flush the radiator on a 2003 International 4300, start by ensuring the engine is cool and then locate the radiator drain valve at the bottom of the radiator. Place a container underneath to catch the old coolant, open the drain valve, and let the coolant flow out. After draining, close the valve and fill the radiator with a mixture of water and radiator flush solution, then run the engine until it reaches operating temperature. Finally, drain the flush solution, refill with the appropriate coolant, and check for leaks.