Tires are often the most neglected part of your car, but they also play a vital role in keeping you safe on the road. That’s why tire makers are reminding people to check the tread on their tires as the summer driving season approaches.

When the tread on tires becomes too worn and tread grooves become too shallow, a tire’s ability to efficiently evacuate water is considerably reduced. That can lead to hydroplaning and can increase the distance it takes for a vehicle to come to a stop.  

“The tread depth of the tire creates traction on the road and out here it rains a lot,” said Don Blythe of OK Tire. “Just be checking your tires and replacing them when they're worn down you can certainly improve your wet traction,”

The legal limit of wear is 1.6 mm or 2/32nds of an inch of tread depth. But most tire makers recommend tires be replaced before the legal limit of wear is reached to ensure better wet-weather stopping power.

A recent U.S. tire study demonstrated how dramatically stopping distances can increase on wet roadways depending on tire wear. The study measured panic stopping distances at highway speeds on wet asphalt, comparing new tires with partially and fully worn tires.  

The shortest stopping distance was on new tires with 8 mm or 10/32nds of an inch of tread depth. In the demonstration, tires three-quarters worn to a tread depth of 3.2 mm or 4/32nds of an inch increased the stopping distance, taking a further seven car lengths to stop. On fully worn tires with tread depth at the legal limit of 1.6 mm or 2/32nds of an inch, the stopping distance was lengthened by yet another seven car lengths.

The simple way to check your tire tread is by using a dime. Insert it into the tread and take a look at how much of the ship's sail you can see.

"If you can see the top of the mast on the Bluenose then the tire is worn down, but you need to really look at your tire before they are totally worn out," said Blythe.

All tires also come with wear bars, which can be more difficult to see. If the wear bar is smooth across the tread in one spot, you need to get your tires changed.

Your tire's air pressure is another important thing to keep an eye on. You should use an air pressure gauge once a month to check that your tires are properly inflated. An under-inflated tire wastes fuel because it doesn't roll as easily as it should. In fact, a recent report found a motorist who drives 20,000 kilometres a year can save as much as 100-dollars in fuel simply by having their tires inflated to the right pressure.