What is "retreads"

Usage examples of "retreads".

Still, when something, when anything was wrong hi town, when a pump was frozen or a cow was sick or the outhouse had blown down, the call went out for Joe Mondragon, who would defy ram, hail, blizzards, tornadoes, and earthquakes hi order to skid his pickup with the four bald retreads and no spare to a stop hi your front yard and have the thing or the animal or whatever it was temporarily patched up and functioning again.