Bald tires are tires which have been so worn down that they have almost no tread. Since tread is what helps tires grip the road, bald tires can be extremely dangerous. Ideally, tires should be replaced before they are truly bald, for optimal safety. Driving with good tires is also easier, and you may notice a marked improvement in vehicle handling after you replace worn tires.
Tires will gradually wear down over the course of routine use. Some things will cause tires to wear down more quickly, such as aggressive driving or steering and alignment problems. The United States Department of Transportation recommends that drivers check their tires every month and before a long trip to ensure that the tire tread depth is safe. In addition, motorists should use a pressure gauge to check the inflation level of their tires, as underinflated tires are dangerous, especially if they have low tread as well.
As a general rule, tires are usable until the tire tread depth reaches 1/16 of an inch (.15 centimeters). In the United States, consumers can use a penny to assess tire safety; insert a penny between the treads of the tire, with Lincoln's head pointing down. If you can see the top of Lincoln's head, replace the tire. Penny coins in many other nations can be used in much the same way. Most tire manufacturers also embed tread wear indicators, which will become visible when a tire needs to be replaced.
The term “bald tires” is very apt, as a truly bald tire really does look bald. The treads on the tire will appear as faint ghosts, rather than strongly marked patterns, and the tire may have a slightly faded, gray look. In a car in good condition, tires should wear evenly, and if you have one bald tire, the tire on the other side of the car should be bald as well. If only one tire appears to be balding, it is an indicator that your car may not be aligned properly, or that someone replaced only one tire at some point, rather than two, as is standard.
Bald tires are dangerous for a number of reasons. In the first place, the limited tread reduces traction for the car, which can be very dangerous in wet or icy driving conditions. Bald tires are also more likely to fail, especially at high speed, since they are worn and stressed. Tire blowouts are generally not enjoyable, and they can be deadly in a high speed driving environment.
In addition to daily wear and tear, some things can accelerate the rate of balding. High speed driving tends to be hard on tires, for example, as does improper inflation, which will also cause uneven wear. Hard cornering may generate uneven wear patterns, and one of the leading causes is improper alignment. Alignment can be checked at an auto repair shop, while driving habits will need to be modified or unlearned if you want to prolong the life of your tires.