There are several signs that may indicate it is time to replace your car’s tires:

1. Tread depth: When the tread on your tires becomes too shallow, it can reduce their traction and handling performance. You can check the tread depth by using a tread depth gauge or by performing the “penny test”: insert a penny into the tread with Lincoln’s head facing down. If you can see the top of Lincoln’s head, it is time to replace your tires.
2. Bulges or blisters: If you notice bulges or blisters on the sidewall of your tires, it is a sign that the tire has been damaged and needs to be replaced.
3. Cracks or cuts: If you see visible cracks or cuts in your tires, it is a sign that they are deteriorating and need to be replaced.
4. Vibrations: If you feel vibrations while driving, it could be a sign that your tires are out of balance or that they have become worn and need to be replaced.
5. Age: Tire tread and performance can degrade over time even if the tires have not been heavily used. It is generally recommended to replace tires after six years of use, or sooner if they show any of the aforementioned signs of wear.

It is important to regularly inspect your tires and replace them as needed to ensure your vehicle is safe to drive and to maintain its handling performance.