I HAVE 1999 F350 PSD. WHEN I DRIVE ON THE HIGHWAY AND GET TO 74 MPH A DINGING SOUND COMES FROM THE FUSE BLOCK UNDER THE DASH. I CAN GO FASTER THAN 74 BUT THE DINGING IS STILL THERE . BUT IF I BACK IT DOWN TO 72 I GOES AWAY . NO ONE CAN SEEM TO FIGURE OUT HOW TO GET RID OF IT
