GM 15751280
Muffler W/Tpipe

First make sure to wear protective goggles and gloves and exercise caution when it comes to exercise service. To replace the Muffler. The Muffler is serviced as an assembly with an Exhaust Pipe and Tail Pipe and if Tail Pipe is after-market it is raised up using the frame to drop the raid axle. Begin by raising the vehicle. Screw out the nuts that fasten the Catalytic Converter pipe to the Muffler flange for a 4.3l engine that has a single Catalytic Converter pipe. For a 4.8l/5.3l/6.0l engine with two Catalytic Converter pipes, loosen the clamp of the right Catalytic Converter and remove the nuts that hold the left Catalytic Converter to the Muffler flange. Remove the Muffler assembly hanger pins from the exhaust hanger insulators based on the wheelbase and exhaust system length of the car, this can be a two person job because of the weight of the exhaust system. Lift the Muffler assembly over the rear axle and pull it towards the front on the vehicle. For installation, place the Muffler assembly from the front of the vehicle by lifting it over the rear axle, which may need two people. Mount the Muffler assembly hanger pins to the exhaust hanger insulators. If fitted with a 4.3l engine, then fit the retaining nuts and new gasket to the front of Muffler and tighten the Catalytic Converter to Muffler retaining nuts to 48 nm (35 ft. Lbs.). For a 4.8l/4.3l/6.0l engine, fit a right Catalytic Converter in the Muffler, and tighten the clamp nut to 54nm(40 ft. Lbs.). Replace a new gasket and right nuts retaining left the Catalytic Converter to the Muffler flange, ensure the exhaust system align properly, then the tighten-right Catalytic Converter clamp to 54 nm (40 ft lbs.) & the Catalytic Converter to the Muffler flange nuts to 48 nm (35 ft lbs.). Finally, lower the vehicle.

You must begin by lifting the vehicle before putting on protective goggles and gloves to guarantee safety. Unscrew the nuts which secure the Exhaust Pipe flange to the catalytic converter pipe and the Exhaust Pipe flange to the Muffler. You should remove the Exhaust Pipe with its two flange gaskets. The installation process requires new gaskets on both the Muffler flange and catalytic converter pipe flange which precedes installing the Exhaust Pipe. Before installing, place new gaskets on both flanges and proceed with the installation of Muffler nuts to Exhaust Pipe then catalytic converter pipe nuts to Exhaust Pipe while tightening the nuts to 48 nm (35 ft. Lbs.). Exhaust system clearance verification together with component alignment checks must be performed prior to lowering the vehicle.

Remove the nuts retaining the exhaust pipe flange to the catalytic converter pipe and the nuts retaining the exhaust pipe flange to the muffler.

Verify the exhaust system for proper clearance and alignment of all components before lowering the vehicle.

Mark the position of the band clamp on the intermediate exhaust pipe, grind the weld to remove it, and install a new band clamp.