This was concerning a different car, but the rule still applies.

I had a vehicle that was starting to overheat. I replace the water pump...the t-stat, flushed the radiator, even new hoses....no joy. I called a repair shop (the mech actually spoke to me over the phone) I told him what I had done, and he asked me a very simple question. He asked, "is your radiator 10 or more years old?" The answer was yes. He said to replace it. He said do NOT have the radiator rodded out or serviced....just replace it.

I did, no problems since then