Front under carriage air dam/splash panel abruptly pulled away from chassis while traveling at high speed (passing). this resulted in pieces of heavy duty plastic breaking off and bouncing under the car, catching on the pavement. disconcerting--i thought at first i blew a tire (lound noise and then sustained wind noise). it appeared the plastic became fatigued and pulled away from the anchoring bolts. dealer parts manager reports that he has replaced several of these...*ak