If you're wondering whether or not your car really needs new tires, chances are it's time to consider getting them. Across America, there are roughly 6 million car accidents a year, and you don't want to be one of them (per River North Collision Repair). The four main causes of auto-body damage are weather, negligence, fender benders, and high-speed collisions, all of which can be prevented or mitigated by having good tires. Here are five warning signs that you need new tires.

Tread Wear

Did you know that you can test the treadwear of your tires by placing the head of a penny into the grooves of your tires? If you can see the top of Lincoln's head, your treads are too shallow and worn, and you should replace the tire. If part of Lincoln's head is covered, then you have more than 2/32 of an inch of tread depth left, which means you can skip getting new tires.

Weather Exposure

If your car has weathered some pretty gnarly conditions, like constant or extreme exposure to the sun, recent flooding in your area, or rapid temperature changes, it may be time to get your tires checked and even replaced.

Aged Tires

Regardless of tread wear, if your tires are at least six years old, it's time to replace them. Most tire manufacturers recommend car owners change their tires at least every 10 years, although the vast majority of them will need new tires long before then.

Uneven Wear

Another way to know that you probably need to replace your tires is if you have uneven wear. For example, if your tire on the back passenger side is more worn than the tire on the right passenger side, it's much safer to drive a vehicle with an even tire tread. This may mean all your tires need to be replaced, but it's better to be safe than sorry.

Leaking Air

Probably the most obvious sign that you need to replace your tires is when you notice a tire is leaking air, even after you put air in it. Often, a small pebble, screw, or rusty nail can be the culprit of a tire leak. In some cases, the tire can be patched, and you can avoid having to replace it. However, most tire experts recommend just replacing the tire, especially if the tire is older or has a good amount of treadwear.

Having tires that are in good shape as evidenced by the good tread, not having been exposed to extreme weather, are relatively young, are evenly worn, and aren't leaking air can prevent you from getting into a wreck. If your tires are showing any of the above signs, it's time to get to your nearest tire store and get your tires replaced.