Having a consistent psi in all four tires also helps with better gas mileage, saving you money.
It's not safe to put the rubber to the road if that rubber is worn and needs replacing. Keeping your tires properly maintained and knowing when to change them can help preserve the life of your car as well as your own!
Rule No. 1: Pump it up. Maintaining the proper pressure per square inch (psi) in your tires is a simple task that is often overlooked. Under-inflated tires create extra drag and wear down the treads. The optimal psi for your vehicle can be found in the owner’s manual and on the doorjamb of most cars. Having a consistent psi in all four tires also helps with better gas mileage, saving you money.
Rule No. 2: Take a test with a president. In the past, you could stick a penny into your treads to check on wear. Using the "penny test," place the penny upside-down in the tread and look for the top of Abraham Lincoln's head to see if your tires have worn down too much. Since 2007, however, road safety tests recommend using a quarter instead — same test, different president. Insert a quarter with George Washington’s head upside-down into your tire’s tread. If you can see the top of of our first president's head, it might be time to get new tires.
Rule No. 3: Be sure to rotate your tires every 6,000-8,000 miles or every six months to ensure equal deterioration on all four sets of treads. In addition, routine alignment checks will guarantee even wear as well as extend the life of your tires.
Rule No. 4: When you get new tires, make sure you get four of the same type and design. If you replace two at a time, be sure to put the newer tires on the back. It might sound counter-intuitive to not put the new treads on the overworked front axle, but, by putting them on the back axle, you are safeguarding against fishtailing and hydroplaning.
Now that you know what to do, get out that air-pressure gauge and check those tires!
