7 warning signs you need new tires

Naturally, when the tread on your tires gets too low, it's time for fresh rubber. An easy way to see if your tread is too low in the US is the penny test. Place a penny in the grooves between the treads on your tires with Lincoln's pointing down. If you can still see the top of Lincoln's head, then the tread is too shallow and new tires are in order.

There will be instances where the tread on a tire wears off at different rates. Sometimes, parts of a tire can look perfectly fine while other parts are worn downs to the cords. Uneven tire wear can be the result of improperly inflated tires, misaligned wheels or even damaged suspension parts.

Weird or excessive noise and vibrations coming from your tires even on smooth roads could be an indicator of a myriad of issues ranging from worn suspension parts to poor wheel alignment to improperly inflated tires. Regardless, it's a sign something is wrong with your car and you should probably have your car looked at by a mechanic. The issue causing the vibration may have damaged the tire or caused uneven tread wear which means they may have to be replaced.

Sometimes bubbles can develop on the sides or even on the threads of tires. The bubbles can be caused by production defects but can also be the result of air getting in between the various internal layers of the tire. Either way, it's time for a new tire.

If the rubber in your tires has cracked, it's time for new tires. Cracks are a sign that the rubber has degraded that can be due to age or improper use.

If you've owned a car a long time and the tires haven't been changed, it's probably time for a fresh set even if they look like there's plenty of tread left. According to Firestone, most vehicle manufacturers recommend replacing your tires every six years while tire manufacturers recommend a fresh set after 10 years.