Transcript for How to know when it's time for new tires
We are back with that new warning about your tires after scenes like this one, cars crashing in these winter storms that are now moving east. ABC's gio Benitez is here and, gio, driving on worn tires in wet conditions is very dangerous. Reporter: Incredibly dangerous, good morning. We know cars are loaded with safety features. They warn us about important things like low tire pressure. But one thing they may not tell you is when you have low tread tires. That's when they have smoothed out and lost grip so "Consumer reports" is out with an urgent warning about worn tires and we are with them for a test drive. They're like scenes straight out of action movies. A hydroplaning accident caught on camera and there's this near crash on wet roads. Experts say many times low tread tires are to blame. People aren't aware so much that as their tires are wearing they're also losing performance in certain areas, wet, snow, ice. Reporter: To show how dangerous low tread tires can be we go to the "Consumer reports" auto test track. Our first demo hydroplaning. That's when tires lose contact with the road. This can happen when your tire has such low tread that it isn't able to disperse the water on the road. A wedge forms in front of the tire and the driver loses the ability to steer. First we try brand-new tires. I'm going to enter the water. Reporter: We approach the slight curve at 50 miles per hour driving through less than an inch of standing water. And I'm able to stay on that curve. You never lost control. Reporter: But it's a different case when we switch to low tread tires. About half the amount as the new ones. Experts say this is when you should start shopping for new channels. There's less channel, less grooves for the water to dissipate from. Reporter: Our car is not able to stay on that curve. We completely lose control of steering. The car wants to go straight. Reporter: Next we try braking in wet conditions. The tire with good grip will stop in a shorter distance. 0 to 60. A panic stop. Reporter: We measure the distance it takes for the car to stop. With the new tires the car stops at 161 feet. But when we hit the track with the low tread tires -- We're going to do the same speed. Reporter: Ryan slams own those brakes again. Wow. That's a significant difference. The car stops at 202 feet. About 40 feet farther than with the new tires. That's more than the length of two cars. These tires are not worn out completely. They're at 4/32. A good time to start looking at new tires. Reporter: A decision that could save a life down the road. It really could. So how do you know when it's time to look for new tires? Well, there is a really easy way. You can use a quarter to measure that tread depth. Check this out. So nothing but love for George Washington but we want to put him upside down and make sure that his head is being sort of cut off there. The top of the head. You don't want tosee hat. That's when you know you have brand-new tires. That's okay. But look at these right here because when you put that quarter here, you can still see the top of George Washington's head so that is now when you need to start looking for new tires. Remember, all season tire, that's about every 50,000 to 60,000 miles when you need to start looking. I see you have more change. You have another tip for us when you have to immediately change the tires. That's right. We'll use a penny. It's so small that we really want to show it's a really worn tire. This one has Abraham Lincoln and look at that. With the penny it is so tiny and still you can see Abraham Lincoln's head. That's when you just can't drive on it could be illegal in some states. Come inside and give us our money back, gio. Thanks. A good message for everybody. Take a few minutes to do that. You can save your life. Especially in this weather.
This transcript has been automatically generated and may not be 100% accurate.