Starting the replacement process first requires wearing protective goggles and gloves along with being mindful of exhaust service precautions. The complete Muffler service includes
Exhaust Pipe installation along with Tail Pipe elements yet aftermarket tail pipes remain optional. Raising the vehicle through the frame system will decrease the height of the rear axle. Owners of vehicles with 4.3l, 5.0l or 5.7l engines should remove the nuts retaining the single
Catalytic Converter pipe at the Muffler flange. Vehicles with 5.0l or 5.7l engines using dual Catalytic Converter pipes and 8.1l engines require users to first loosen the right Catalytic Converter clamp then remove the nuts that secure the left Catalytic Converter to the Muffler flange. Nuts securing the Exhaust Pipe to the Muffler flange need removal on a 6.5l engine. These next procedures depend on the vehicle's wheelbase along with the length of the exhaust system: the removal process for a 4.3l, 5.0l, and 5.7l engine requires two people due to weight limitations for stripping hanger pins from exhaust hanger insulators on vehicles with this 135-inch wheelbase. Once in position over the rear axle lift the Muffler assembly towards the front for removal. The procedure for a 155-inch wheelbase requires a suitable jack stand to support the right side of the rear axle followed by shock absorber tension relief and right lower shock absorber bolt and nut removal then axle lowering until the Muffler assembly hanger pins can be taken out before the assembly lift towards the front. When performing a 139-inch, 159-inch, or 177-inch wheelbase cutaway body repair you must support the rear axle to lower tension on the rear springs before removing the tire assembly and all rear spring u-bolts along with anchor plate components. Next, remove the right lower shock absorber bolt and nut and lower the axle for installation of the Muffler assembly pins by lifting the assembly over the rear axle towards the rear. Installation begins by lifting the Muffler assembly forward from the front for vehicles running 4.3l, 5.0l or 5.7l engines equipped with 135-inch wheels. Install the hanger pins afterward. The installation sequence begins again with a 155-inch wheelbase. Base the rear axle with a secure jack to install the lower shock absorber bolt and nut before clamping it to 80 nm (59 ft. Lbs.) then remove the jack stand. Install hanger pins first then position the Muffler assembly from the rear before raising the right side of the rear axle to install lower shock absorber bolt and nut with torque to 80 nm (59 ft. Lbs.) for 139-inch, 159-inch, 177-inch wheelbase cutaway body style vehicles. Apply tension to the inner u-bolt nuts first and then to the outer u-bolt nuts at 25 nm (18 ft. Lbs.). Then tighten all the u-bolt nuts to either 95 nm (70 ft. Lbs.) for vehicles under 7300 gvw or 150 nm (111 ft. Lbs.) for vehicles above 7300 gvw. Install the tire and wheel. If your vehicle operates with either a 4.3l, 5.0l or 5.7l motor using single Catalytic Converter pipes you must attach the front Muffler retaining nuts and new gasket before tightening them to 48 nm (35 ft. Lbs.). A proper installation process begins by placing the right Catalytic Converter within the Muffler conduit before fitting new gaskets and nuts to maintain left Catalytic Converter alignment with the Muffler flange. Properly align and tighten right Catalytic Converter clamps to 54 nm (40 ft. Lbs.) and Muffler flange nuts to 48 nm (35 ft. Lbs.). A 6.5l engine requires new gasket installation along with Muffler flange Exhaust Pipe nut tightening at 48 nm (35 ft. Lbs.). After lowering the vehicle check the exhaust system to ensure proper fitment and alignment.