Thread: When Should Tires Be Replaced Even If They Do Not Show Wear? When Should Tires Be Replaced Even If They Do Not Show Wear? This question has to do with a 2001 Dyna FXD Super Glide which does not get used a lot, it has just over 4000 miles on it. I replaced the tires after the first 5 years and now I'm thinking about doing it again.