How to Tell If You Need New Tires
There are two main reasons that tires typically need to be replaced.
Don’t wait until your tread has been worn completely from the surface of your tires before you get around to replacing them. This is commonly known as “bald” tires and is a very dangerous condition. Tires are generally rated to last a set amount of miles when you buy them. However other factors can reduce the service life of your tires, such as driving conditions and habits.
Many states have laws requiring car tires to carry a minimum amount of tread depth to be legal on the road. That is because bald tires have a very hard time maintaining traction, especially in wet conditions. In short, they’re unsafe. If new tires are a purchase that may stretch your budget to the breaking point, then your best bet is to plan for the extra cost. Keep track of your tire’s wear levels.
Ask the mechanic at the service station to measure and record the tread depth of your tires when you change your oil. That will give you plenty of warning when it’s almost time to get them replaced. You can also perform a check yourself. You don’t need anything fancy like a tread depth gauge. All you need is a penny. Hold the penny so that Lincoln’s head is facing the surface of the tire, and place the penny in several of the tread grooves in different places on each tire. As a rule of thumb, if the tread is deeper than the top of Lincoln’s head, you’re ok. However, if you’re anywhere close you might want to start making plans for replacement.
Unfortunately it isn’t a perfect world, and tires don’t last for their whole service life all the time. Often road damage sends tires into retirement long before their intended service life is over. The most common road damage is a fault in the tire’s sidewall. Once the sidewall of the tire is compromised, the tire is at very high risk for blowout. Look for bubbles in the rubber of the sidewall, it will generally look like a marble or small ball buried under the rubber surface of the tire. Also check the sidewalls for chips and cuts in the rubber.
Sidewall damage is irreparable. You will always have to replace a tire whose sidewall has been damaged. You can also inspect the tread of the tire for deep cuts or faults, but generally you only have to worry about this part of the tire if a problem has become apparent while you are driving (i.e. excessive vibration at speed).