To replace the Muffler for 6.0l, 6.6l and 8.1l engines, lift and hold the vehicle and remove spare tire if necessary. Put adjustable jack stands under rear axle and if your vehicle comes with an 8.6 inch or 9.5 inch ring gear, remove rear axle vent hose and its swivel clip from the rear brake crossover pipe. Repeat the same process for a 10.5 inch ring gear. Lower the rear axle if necessary by removing the lower bolts and nuts of rear
Shock Absorbers. For 6.0l or 8.1l engines, undo exhaust Muffler nuts and unbolt the
Exhaust Pipe clamp. With help, support the exhaust Muffler and unscrew the nuts for the 6.6. Engine. Slide the Muffler rearward to remove it from the
Catalytic Converter, taking the insulators off the frame hangers as required. If the Muffler is not to be done as an assembly, position the band clamp of the intermediate Exhaust Pipe, then grind the weld from the band to remove it, and the new band clamp. For installation, when the Muffler was replaced on 6.0l or 8.1l engines, apply the old
Oxygen Sensor with the anti-seize compound gm p/n 12377953, tighten to 42 nm (31 ft. Lbs). Apply lubrication to insulators for the easy installation and then mount them on Muffler hangers for 6.6l engines followed by a new exhaust Muffler gasket. Push the Muffler forward to attach it to the Muffler pipe of the exhaust and attach the insulators to the hangers of the frame. Install the insulators on the Muffler hangers and a new exhaust manifold pipe gasket, when you have 6.0l or 8.1l engines. Pull the Muffler forward to attach it to the Catalytic Converter, fit the insulators to the frame hangers, and to the 6.6l engines, install and tighten the Muffler nuts to 40 nm (30 ft.lbs.). Position the new band clamp on the intermediate Exhaust Pipe, so the bolt is not underneath the pipe, installing and tighten the exhaust Muffler nuts as well as the Exhaust Pipe clamp bolt to the specifications of 40 nm (30 ft. Lbs.) and 44 nm (33 ft. Lbs), respectively. Raise the rear axle and install the rear shock absorbers lower bolts and nuts while tightening them up to 95 nm (70 ft. Lbs) and reconnecting the rear axle vent hose and swivel clips if necessary. Finally, take off the adjustable jack stands, replace the spare tire if necessary, and lower the car.