There are differences in safety and grip between retreaded tires and new tires. Refurbished tires are made by shoveling a layer of rubber off the tire surface and then re-carving the pattern. The safety of such tires will be greatly reduced. It is recommended that you do not buy retreaded tires. The tire is the only part of the car that touches the ground, which is related to the driving stability and safety of the car. Tires are rubber products, and rubber products will age after long-term use, so it is necessary to replace tires regularly. Under normal circumstances, the tires installed on the car can be used for four years, so it is recommended that you replace the tires every four years. Buying new tires must depend on the date of production, because tires also have a shelf life. In general, the shelf life of tires is three years. Don't buy it after delivery for more than three years. After installing new tires, it is recommended that you carry out a dynamic balance test on each wheel to prevent the wheels from shaking abnormally when driving at high speed. If the wheels shake abnormally when driving at high speed, it will affect the handling and driving stability of the car. Usually use the car, everyone must always check the tire pressure. The air pressure should not be too high or too low. Excessive air pressure will cause tires. The contact area with the ground becomes smaller. If the air pressure is too low, the tire will deform in waves.