Check out what Consumer Reports says about the Ranger vs. its closest competitors.
I'd give a link, but you have to be a subscriber. If you're not a subscriber, it's money well spent before you make any large purchases.
If you got a new truck every four years, you just might have lucked out and traded them before the cooling problems manifested themselves, especially if you only drive them a few thousand miles.
Or, you just could be exceptionally lucky. If so, congratulations.