James Bond has them, the Hummers have them, most truckers have them and the military have them for years. The self-inflating tires allow the vehicle to fit the current terrain for optimal performance and safety under those conditions.
Currently, many consumer vehicles are equipped with pressure monitoring systems, but there is no way for the driver to do anything about it without an external air source. There are many auto inflatable tire systems on the market, but most of them are only available for commercial and military applications. The exception, of course, is the CTIS system in the Hummer.
Basics of tire inflation
According to AAA, about 80 percent of the cars on the highway are driving with one or more under inflated tires. Tires lose air through normal conduction (especially after hitting pot holes or curbs), permeation, and seasonal temperature changes. They may lose one or two psi (pounds per square inch) each month in the winter and even more in the summer. And, you can not tell if they are properly inflated just by looking at them. You have to use a tire pressure gauge. Not only is bad inflation for your tires, but it is also bad for your gas mileage, it affects the way your car drives and is generally unsafe.
When the tires are inflated, the tread wears out more quickly. According to Goodyear, this equates to 15 percent fewer miles than you can drive on them for every 20 percent you are under inflated. Deflated tires also overheat more quickly than properly inflated tires, which causes more tire damage. Areas faded below indicate areas of excessive tread wear.