How much does tire pressure increase when driving on the highway?
3 Answers
Tire pressure increases by 0.4 to 0.6 bar when driving on the highway. The normal tire pressure temperature is between 2.2 and 2.4 bar, and tire pressure rises as the temperature increases. During high-speed driving, especially during emergency braking and rapid acceleration, tire temperature rises quickly. For every 10-degree increase in tire pressure temperature, the pressure increases by 0.1 bar. Therefore, maintaining tire pressure at the standard value helps avoid blowouts during high-speed driving and emergency braking. During long-distance driving, the tires generate heat from prolonged friction, and tire pressure increases in high-temperature environments. It is not advisable to lower tire pressure excessively to prevent blowouts, as excessively low tire pressure can also lead to blowouts. Low tire pressure increases the contact area between the tire and the ground, putting more pressure on the tire shoulders, which generates heat through internal friction, consumes the gas inside the tire, and damages its internal structure.
Generally, tire pressure increases by 0.3 to 0.5 bar when driving on highways. With 20 years of driving experience and frequent long-distance deliveries, I've measured that if the cold tire pressure is 2.5 bar, it can rise to around 2.8 bar after two hours of highway driving. The increase is even more significant in summer, especially for heavy trucks carrying heavy loads. This is mainly due to heat generated by tire friction causing gas expansion. The key is to check the cold tire pressure in advance to ensure it meets the manufacturer's recommended value. Insufficient tire pressure can actually increase friction, leading to faster and more dangerous temperature rises. After reaching the destination, the tire pressure will drop again as the tires cool down. Remember to regularly check tire conditions with a tire pressure gauge to ensure safety.
As a frequent long-distance cross-province driver, I pay special attention to tire pressure changes. Typically, high-speed driving can increase tire pressure by 0.3 to 0.4 bar, with the exact amount depending on vehicle speed. My car is equipped with a tire pressure monitoring system, and maintaining 120 km/h for half an hour can raise the pressure from 2.5 to 2.8 bar. Temperature is also a crucial factor, with more noticeable increases on scorching summer roads. Once during a fully loaded summer trip, the pressure rose by 0.6 bar, prompting me to immediately pull into a service area for cooling. I recommend adjusting cold tire pressure accurately before departure and monitoring vehicle conditions during the journey. Maintaining proper tire pressure also improves fuel efficiency, making it highly practical for family long-distance travel.
