THREAD WEAR INDICATOR
One sign that you need to change tires is when tire wear reaches the T.W.I or Thread Wear Indicator. You can find this indicator at the sidewall and threads of the tire.
The thread wear indicator usually has Δ(Triangle Symbol) on it with a T.W.I emboss letters on the sidewall and a bar on the threads.
When your tire wear reaches the top of the triangle or the top of the bar, then it is a sign that you need to change tires.
OTHER SIGNS TO CHANGE TIRES
- Cracks on the tires
- Tire is more than 6 years
- Tire already has deformity
- Tire has big holes