About 13 percent of vehicles have at least one bald tire, according to a recent survey by the Rubber Manufacturers Association (RMA). When it comes to car tires, bald is not beautiful. It is dangerous.
These findings mark an increase from the 10.4 percent found in a similar survey done in 2010. As RMA points out--and we have corroborated with our own testing--all-weather grip is greatly diminished at the time a tire is worn out. As a tire wears, wet grip, resistance to hydroplaning, and snow traction are negatively affected.
Consumers are shortchanging their safety and that of others when driving on worn-out tires. We urge consumers to check their tire's inflation monthly and to visually check the tires for wear. And it's simple to do. Use a quarter and insert the top of George Washington's head into each of the tread grooves of a tire. If the top of his head is just level with tread, then it's likely the tire has just 4/32-inch of tread depth. Use this as a reason to start shopping for new tires.
With tires this worn, though, you still have tread depth left for some all-weather grip. But now you go from the quarter test to the penny test. Place the penny with Lincoln's head facing into the tread groove. If the top of his head is all visible in anyone of the grooves, the tire is worn-out and should be replaced immediately. No coins available? You can still visually check the tread and look for the raised tread wear bars in the tread grooves. If the bars are flush with the tread, your tire is worn-out.
To keep tire wear even, it's always best to rotate your tires regularly. Most car manuals provide information on recommended rotation intervals and how to rotate them. If you rotate religiously, you can extend tire life and replace all of them with four new ones at once, which will provide the best balance of handing and grip.
Maintaining inflation pressure to the recommended vehicle specification (typically found on a driver's door jamb placard) will help maintain even wear across the width of tire's tread. If you need only two tires, be sure to have the new tires placed in the rear positions and place the worn tires in the front to maintain secure handling.