
Tire pressure is best when it falls within the normal range. The normal tire pressure for car tires is between 230-250kpa. However, the specific normal tire pressure for a car should be based on the manufacturer's recommended value, which can usually be found in the car's user manual, on the label near the driver's door (B-pillar), in the drawer next to the driver's seat, or on the small door of the fuel tank cap. These sources will provide detailed information on the specific tire pressure recommended for use. According to the international GBT2978-2008 standard, the tire pressure for different types of tires is as follows: Standard tires: 2.4-2.5bar; Reinforced tires: 2.8-2.9bar; Maximum pressure: should not exceed 3.5bar. In winter, the tire pressure should be based on the standard tire pressure of the car, with an appropriate increase of about 0.2bar. Generally, the lower limit of the standard tire pressure for car tires is sufficient. For example, the lower limit for standard tires is 2.4bar. If the car is often parked outdoors, the tire pressure can generally be about 0.1bar lower than the standard to avoid tire blowouts due to high temperatures.

I always pay close attention to tire pressure when driving, and the manufacturer's recommended values are the most reliable, usually found on the door frame label or in the manual. For example, my SUV recommends around 2.3 bar. Before long highway drives in summer, I reduce it to 2.2 to avoid overheating and blowouts, while in winter, I inflate to 2.4 for better traction. Remember to check tire pressure when the tires are cold—measuring after driving will give higher readings. Last time, I inflated to 2.6, and the ride over speed bumps became harsh with noticeable shoulder wear; dropping to 1.9 made the steering feel loose and increased fuel consumption. When carrying heavy loads, I add an extra 0.2 to prevent rapid sidewall wear.

The biggest fear on long-distance drives is tire problems. When I'm on the highway, I always keep the tire pressure 0.1-0.2 bar higher than the standard. It's not just random tinkering – once when I was traveling with my family and didn't pay attention, the tire pressure was only 2.0. Not only did the tires feel scorching hot at the rest area, but the fuel consumption also increased by a full liter per 100 kilometers. Now it's a habit: whenever I get free air at gas stations, I ask them to inflate to the manufacturer's upper limit. For example, my car's recommended range is 2.3-2.5, so I go for 2.5. When the tire pressure monitoring system shows 2.5, it indeed saves fuel – with less tire contact area, resistance naturally decreases. However, on rough roads, I slightly reduce it to 2.4, as it's too bumpy and uncomfortable otherwise.

With 20 years of car repair experience, I can tell if a tire is flat just by looking, but it's best not to rely on visual inspection alone. Always keep a mechanical tire pressure gauge in your toolkit, and measure the pressure in the morning before the car is driven for the most accurate reading. For passenger cars, the pressure typically ranges between 2.2 and 2.5 bar. In summer, for every 8-degree rise in tire temperature, the pressure increases by about 0.1 bar. When a customer brings in a performance car, I recommend maintaining the upper limit to enhance cornering support. For families with elderly or children, adjusting to the lower limit makes the suspension softer. Additionally, run-flat tires should be inflated about 0.2 bar higher than regular tires, as their run-flat design requires higher pressure to support the vehicle's weight.


