A lot depends on how well the vehicle is maintained. (using the correct coolant at the proper % and changing it on schedule) If original, your vehicle has a heavy duty truck radiator installed which is generally good until the day it's not good, which depends on the above. If mine, I would keep a sharp eye on the radiator, belts, hoses, (especially the upper radiator hose) water pump seal, fan clutch, and the coolant expansion tank (which tends to crack) at +-15 years and beyond.
Although it does happen, cooling system components rarely fail catastrophically without warning. If you see/hear/smell leaks, bulging, cracks, grinding, squealing, overtemps or variability on the temp gauge, STOP IMMEDIATELY, and figure out why. IMO, it would be a good idea to source, price, and check the availability of the major components now so that you don't get blindsided in the near future.
To get an idea of the condition inside your radiator, look through the open cap and at the opaque plastic walls of the coolant expansion tank. If the inside of the tank is coated with rust, scum, and other lovely unmentionables, chances are your radiator is too.
Chum lee