Lower temperatures cause the air pressure inside pneumatic tires to decrease. This is a direct result of the ideal gas law, which states that pressure is proportional to temperature when volume is held constant. For example, a tire inflated to 35 psi at 70F (21C) could drop to 30 psi at 32F (0C).
Understanding this pressure fluctuation is critical for vehicle safety and optimal performance. Underinflation can lead to increased tire wear, reduced fuel efficiency, and impaired handling. Historically, this phenomenon has been a consistent factor in vehicle operation, particularly in regions with significant seasonal temperature changes. Correct tire pressure ensures proper contact with the road surface, contributing to safer braking distances and predictable steering response. Furthermore, maintaining recommended pressure minimizes rolling resistance, which directly impacts fuel economy.
