The TPMS failed. The valve stem cracked off when adding air. Air was being added because the valve stem was leaking, and the tire was near flat, and I wanted to take it to a repair shop. This is the second TPMS valve failure I have had. Fortunately, both occurred at a standstill. I see tales on the internet of failure at high speed, followed by vary rapid decompression and tire failure. Expensive, if not unsafe. In my own case, with over 50 years driving experience and 2 years as a mechanic, I have never seen a valve stem failure before. Now, I have two. Expert mechanics are advising to replace them with standard valves, and I will. From an economic view, the several failures of the stems, and stem failures, have cost me about 6 cents per mile. Gas has cost me about 18 cents per mile (at todays cost). Thus, the TPMS system maintenance is about 1/3 of the gas cost. I doubt very seriously that the TPMS system saves that much in gasoline use. But from a safety perspective, I am not willing to risk sudden depressurization followed by tire destruction at highway speeds. Thus, I will be pulling those out before my next highway trip. After talking with several mechanics, looking at the designs, and looking at experiences of others, I conclude that TPMS is a good idea with a bad execution. If they are not (nearly as secure) as older valve stems, they should be de-mandated. Finally, I note that at least some of these have Mercury in the package as a rotary switch. As much as we are spending to remove Mercury from the environment...

- Columbus, OH, USA

The tire pressure monitoring system has experienced a failure on the left front tire while traveling under 30mph, could have cause potential hazarous situation if occurred at higher rate of speed.

- Yorkville, IL, USA