THIS PRELIMINARY INFORMATION COMMUNICATION PROVIDES INFORMATION TO THE TECHNICIAN ABOUT VEHICLES THAT HAVE NOISE FROM THE EXHAUST. TECHNICIAN MAY FIND THE LEFT HAND CATALYTIC CONVERTER PIPE CRACKING NEAR CYLINDER HEAD MOUNTING FLANGE WELD. TECHNICIAN WILL NEED TO REPLACE THE CATALYTIC CONVERTER WITH LATEST PART NUMBER FROM GENERAL MOTORS SERVICE PARTS OPERATIONS. GENERAL MOTORS IS WORKING ON A SOLUTION FOR THIS CONCERN.