I know, no one ever want to think about buying tires. There is nothing less enjoyable than spending your vacation money on something you can't even admire. But think of if this way. You and your family's safety depends on it. You should check your tires at least once a month and before and after long trips. To determine whether you need to buy new tires, have your wheels balanced or have your vehicle aligned.
Underinflated tires wear out faster, create excessive heat, decrease fuel mileage, and make your vehicle much harder to handle. Overinflated tires can blow out more easily, wear out faster, and make the car unstable and unsafe to handle. New tires on a vehicle out of alignment can wear out as quickly as 5000 miles!
Look for things in each tire.
Do you see nails, stones, or other debris in the treads? Remove them. But if you're going to remove a nail, first make sure that your spare tire is inflated and in usable shape. If you hear a hissing sound when you pull a nail, push the nail back in quickly and take the tire to be fixed. If you aren't sure whether air is escaping, put some soapy water on the hole and look for the bubbles made by escaping air. If you're still not sure whether the nail may have caused a leak, check your air pressure and then check it again the next day to see whether it's lower. Tires with leaks should be patched by a professional. If the leak persists, get a new tire.
Look at the sidewalls.
Check for deeply scuffed or worn areas, bulges or bubbles, small slits, or holes. Do the tires fit evenly and snugly around the wheel? Tires will show signs of cracking around the wheels as they age. This is caused by tires drying out and "dry rotting." When this is present tires will need to replaced as soon as possible to prevent a blowout.
Look at the tread.
Most tires have tread-wear indicators built into them . These bars of hard rubber are normally invisible at first look, but appear across treads that have been worn down to 1/16th of an inch of the surface of the tire. If these indicators appear in two or three different places, replace the tire. If your tires don't show these indicators and you think that they may be worn too low, place a Lincoln penny head down in the groove between the treads. If you can see the top of Lincoln's head, your tire probably needs to be replaced. To measure tread wear more exactly, place a thin ruler into the tread and measure the distance from the base of the tread to the surface. It should be more than 1/16 inch deep. If your front tires are more worn than your rear ones and show abnormal wear patterns, you probably need to have your wheels aligned.
This a a few things you can do to keep ahead of the curve so to speak. If you feel you need further assistance, check with your loacal garge. I am sure they will be glad to help.