An exhaust leak may develop due to cracked welds on the front catalytic converter. Replacement of the catalyst is recommended; re-welding of the catalyst is discouraged because it is an emissions device.
Car Problem Reports
Mercedes-Benz ML430 Welds May Crack on Front Catalytic Converter
Mercedes-Benz ML430 Problem
Average Mileage: 77,000 mi (73,000 mi - 81,000 mi)