Tire Pressure Monitoring System problems of the 2008 Ford F-250

2008 Ford f250 has a problem with the tire pressure sensor system. The consumer stated an alarm message appeared as if the tires had low pressure. Within the last 18 months, the consumer stated there had been six alarm messages. Two were for out of specifications pressure and four were for sensor fault. In each case of the pressure alarm, all four tires were within 2 psi of each other. Which was verified by the dealer. The consumer was informed the sensor needed to be trained in the dealers shop. Once it was done the problem ceased. The problem seemed to recur after tire rotation, however only under certain circumstances. No alarm was forthcoming while driving around town, but as soon as the consumer drove on the interstate and traveled approximately 4 miles at 65 mph, the alarm activated. The consumer was given several explanations as to why it was happening. He was first told it was his cell phone causing the problem, but the problem persisted, next he was told that the tires should be inflated with nitrogen, as it would stop the pressure variations and avoid the alarm. 2 sensors were replaced. Updated 08/07/09. The consumer was told the system was designed that way and no problem existed. Updated 08/20/09.