My upper radiator hose raptured, not the kind they predicted on mya21st LOL, but steam came out of my hood; good thing I was close to myhouse. Redid the entire coolant system cause I don;t want to take any chances. I think it's not so much the mileage but age (almot 8 years old at that time).
If you don't see the temp went up, I don't see how you'll have problem like crack engine block etc.