There are numerous sources of data that point out the fact that cars and trucks on the road have tire pressures that are significantly lower than recommended by the vehicle manufacturer. Having low tire pressure has many disadvantages. Tires with low pressure generate more heat and can fail, which is more probable and dangerous at high speed. In addition, low tire pressure is unsafe because it can adversely affect vehicle handling, including cornering and braking. Low tire pressure has also been shown to reduce tire life and fuel economy.
The importance of proper tire pressure has led to the commonplace use of tire pressure monitoring devices, which let the driver know when a tire has a pressure below a certain threshold. These systems are useful in that they identify the tire pressure problem, but they do not solve it. Time, effort and tire inflation equipment is required to add air to the tire. Other systems, used in military and commercial vehicles, maintain the proper tire pressure at all times, but are expensive and require special axle and/or hub components.