I WAS DRIVING ON A HIGHWAY AROUND 10:30PM, AND ALL OF A SUDDEN I HEAR GRINDING NOISE AND VSC/TRAC LIGHT GOES ON. REDUCED SPEED BECAUSE I FELT AS THOUGH I MAY LOSE CONTROL OF VEHICLE. VSC/TRAC LIGHT STAYS ON, THEN GOES OFF. LESS THAN 30 MINUTES LATER, I HEAR BEEPING NOISE AND VSC/TRAC LIGHT COMES BACK ON. THIS SAME INCIDENT HAS HAPPENED A WEEK AGO, WHERE I PULLED OVER THE SIDE OF THE ROAD THINKING IT WAS A FLAT BECAUSE I FELT LIKE I WAS LOSING CONTROL THEN TOO, BUT NO FLAT. TRAC CONTROL ISSUE THEN TOO (HEARING GRINDING NOISE). CONCERNED BECAUSE IT SEEMS I MAY LOSE CONTROL. *TR