What is the normal pressure difference between four tires?
3 Answers
The normal pressure difference between four tires should be within 0.1bar. However, it is not necessary to adjust immediately if the difference exceeds 0.1bar, as the error in tire pressure monitoring and different vehicle load conditions may temporarily cause variations in tire pressure. Tire pressure monitoring is a system that automatically and continuously monitors the air pressure in tires while driving, alerting the driver to leaks or low pressure to ensure driving safety. There are three common types of tire pressure monitoring systems: Direct TPMS: Direct TPMS uses pressure sensors installed in each tire to directly measure the tire pressure. The pressure information is transmitted wirelessly from inside the tire to a central receiver module, which then displays the data for each tire. The system automatically alerts the driver when the tire pressure is too low or there is a leak. Indirect TPMS: When the pressure in a tire decreases, the vehicle's weight causes the rolling radius of that tire to become smaller, making it rotate faster than the other wheels. By comparing the rotational speed differences between tires, the system monitors tire pressure. Indirect TPMS essentially relies on calculating the rolling radius of tires to monitor pressure. Tire Pressure Monitoring System (TPMS) Introduction: This system combines the advantages of both the above systems. It equips direct sensors in two diagonally opposite tires and includes a 4-wheel indirect system. Compared to a full direct system, this hybrid system reduces costs and overcomes the limitation of indirect systems, which cannot detect simultaneous low pressure in multiple tires. However, it still cannot provide real-time data of the actual pressure in all four tires as a direct system does.
After driving for so many years, I’ve learned that tire pressure is something you really can’t take lightly. Generally speaking, a difference of 2 to 3 PSI between the four tires is normal, so there’s no need to overreact. Once, I checked my tire pressure and found a difference of over 5 PSI, which caused the car to pull to one side and made driving unstable. This issue not only affects handling but also leads to uneven tire wear, cutting the tire’s lifespan in half. To save money and fuel, I recommend regularly using a tire pressure gauge when the tires are cold to ensure each one is close to the manufacturer’s recommended value. If the difference exceeds 4 PSI, check for leaks or visit a repair shop immediately. Remember, safety comes first—small issues can lead to big mistakes.
From my perspective, maintaining a tire pressure difference within 2 PSI is ideal; anything higher is abnormal. When the difference exceeds 4 PSI, you should suspect a slow leak, which can cause unstable handling and increased fuel consumption. Don't ignore uneven tire pressure, as it can lead to premature tire wear, especially when the pressure difference between front and rear tires is significant. You can easily check it yourself with a simple tire pressure gauge when the tires are cold, and do this every few months. If the difference is extreme, it's time to visit a shop to check for issues with the valve core or wheel rim.
