4.8 & 6.0 LITER. Muffler w/tpipe gasket. Exc.School Bus. Exhaust Pipe Connector Gasket. Gasket for Catalytic Converter System. Gasket for Exhaust Muffler. Over GVW 8,500 Lbs. School Bus. Under GVW 8,500 Lbs. CTLTC CONV. and Amplifier. Catalytic cnvrtr. Exhaust Connector. Muffler w/t.