Cooling issue in 1995 Ford econoline 250?

The radiator isn't going to rust that quickly, but it is a 15 year old truck. Park it on a clean space & leave it run, & see if anything is dripping... Also, after you dump the coolant, keep the expansion tank topped-off. Check it every day or two, & fill it as needed, until it doesn't drop. Once you have filled the radiator, don't pop the cap again, just the expansion tank.