Checking tires regularly improves safety and helps increase fuel economy. Take the tire inspection monthly and before you start each long journey.
Check for cracks due to tire life and due to environmental exposure. Roadside bumps, potholes and other obstacles on the road can lead to cuts and puffs on your car tire sidewalls. Replace tires when there are any signs of damage that cannot be repaired.
The date code tells you when the tire was manufactured. Search for "DOT" followed by a few digits near the wheel. The last four numbers determine when tire was made. For example, the digits "0308" indicate that tire was manufactured in the third week of 2008. Some car manufacturers recommend changing tires after six years. There is no limit, we recommend removing the tire after 10 years, including spare parts, regardless of usage conditions.
You can apply a common method that is using a coin (25-cent US coin) to measure the depth of tire tread. Put the coin upside down in a tire groove. The distance from the edge of the coin to George Washington's hairline is about 4⁄32 inches. If you can see the entire head of Washington, it's time to start buying a new tire to replace, because your car tire only have a bit of traction. And if there is a gap exposed on George's head, check the tire by 1-cent US coin. Still using the same method, it's inserting that coin into the tire groove and turning Lincoln's head down. If you can still see the top of Abe's head through the tread, the tire should be replaced immediately. For many states in the United States it would be illegal to use tires with such tire tread.
And this is an inspection that cannot be ignored. Your tires will lose air over time. They need to be checked monthly and inflated regularly, especially when temperature drops during the winter months. Underinflated tire will bend more than the properly inflated tire. That will cause heat accumulation, which can lead to damage. In addition, low pressure tires have less fuel economy and can wear faster.
To get a good tire pressure index, check when the tire is "cold", meaning the car has been parked for longer than 3 hours. Refer to the vehicle owner's manual and the indications on car door for proper tire pressure. If you have a spare tire, you should regularly check its pressure in case you need it on the itinerary.