The most common problem with your engine’s radiator is a leak. A leak is obvious enough to detect and can usually be fixed quite easily. If you find any engine coolant/antifreeze leaking from your engine, have your vehicle inspected for any leaks or damaged radiator hoses.
When you have your engine flushed or your antifreeze changed, you should have your radiator inspected. Your antifreeze should be changed every two years or 30,000 miles.