The obvious time to replace a tire is when it will no longer hold air or the tread wears out.
The rubber in most tires will last at least 5 to 6 years. Keep in mind that heavy use will reduce the time the tread or sidewall of a tire can survive. In the case of wheelbarrow, golf cart, mower and hand truck tires, people usually use them until they completely wear out, but this may be dangerous. It is very important to be aware of the condition of any tire used on the highway at high speeds. Any tire used on highways will have wear bars built into the tread. WHEN THOSE BARS SHOW, REPLACE THE TIRE!
Things to look for when making a decision as to replace your tires are:
- Cracking on the side wall and bead
- Extreme wear on the tread
- Frequent punctures