Winter weather has now covered much of the United States, and while your tires may not be legally worn out, they may not be suitable for wintertime driving. If you're like many, you simply look at your tires to see if there's enough tread remaining. However, when is the right time to change them?
Although tires aren't legally worn out until they reach 2/32" of remaining tread, snow traction and the evacuation of water and slush become diminished many miles before this. If you are entering the winter season with a partially worn set of all-season or winter tires, Tire Rack recommends drivers consider replacing their tires when they reach approximately 6/32" of remaining tread depth to maintain good mobility. Tires need more tread depth in wintry conditions to compress snow in their grooves and release it as they roll. Without sufficient tread depth, tires do not have enough biting edges and shallower circumferential grooves to effectively evacuate deep snow and slush.
The illustration below shows tires (from left to right) at new tread depth, worn to 6/32" and then worn to 2/32". You can see as the tire approaches 6/32" the tread blocks are noticeably smaller, circumferential grooves are shallower and the sipings for ice traction are much smaller. At 2/32" of remaining tread depth, the tread blocks are almost worn smooth and siping has been lost. With little height left in the circumferential grooves, tire's will hydroplane much easier.
Winter weather is here and it's important to check your tread depth and remember 6/32" or more of remaining tread depth will be needed this winter season. If you need new tires, be sure to use our Survey Results and Test Results to assist you in finding the best wintertime performers.