Keep yourself safe by taking a few minutes to check your tire pressure, alignment, rotation, and tread. You should check the inflation on your tires once a month and check them when your tires are cool, to get the most accurate result. If your car’s suspension system is out of alignment, you will generally feel a pull to one direction while driving. This can be detrimental as it can cause uneven wearing on your tires. Look to your owner’s manual to check how often your tires should be rotated. A rule of thumb to extend the life of your tires would be to rotate them every 5,000 miles. Lastly, check the tread of your tires by placing a penny Lincoln head down in the tread. If the tread is below 2/32 inch (or you can see all of Lincoln’s head), you need to replace your tire.
http://www.rma.org/tire_safety/
tire_maintenance_and_safety/how_to_take_care_of_your_tires/#1
