To change the Muffler, it is essential to use protective goggles and gloves so that if you fall rust and sharp edges might cause injury, and also wait for the exhaust system to cool when servicing to avoid being burnt. Start with lifting the vehicle and supporting the Muffler assembly. Loosen the 3 nuts holding the Muffler assembly to the
Catalytic Converter assembly. To make removal easier, apply lubricant (GM P/N 12345884) to the rubber hangers of the Muffler unit and remove it from the front and rear and tailpipe hangers before detaching it from the vehicle. During installation, check to be sure the exhaust system is aligned properly and leave the bolts or nuts loose until the alignment is correct, then tighten them finger tight from front to rear. Change the worn exhaust system longs, window bracket and clamps to maintain alignment. Make sure to apply replacement parts that are up to oem standards in order to replace the Muffler it's important to replace the tailpipe as well and do this by using new nuts on connecting the Exhaust Pipe to the
Exhaust Manifold while cleaning the manifold stud thread with a wire brush first. Re-lubricate the rubber hangers using rubber lubricant (GM P/N 12345884) before mounting it on the vehicle and connecting the Muffler assembly to the rear hanger, tailpipe hanger, and front hanger. Finally, install the 3 nuts connecting Muffler assembly and Catalytic Converter assembly, and tighten them to 40 nm (30 ft. Lbs).