The process of replacing the right-side Catalytic Converter on the 2500 series starts with hoisting the vehicle into a proper position for access. First loosen the 2 rear oil pan skid plate bolts then remove the 2 front oil pad skid plate bolts before taking off the skid plate if your vehicle has this component. The next step involves taking out both the
Muffler and the transmission crossmember. Remove the right front connector position assurance (CPA) retainer and disconnect the right front heated
Oxygen Sensor (HO2S) electrical connector that connects to the engine wiring harness electrical connector. Separate the right rear cpa retainer before unconnecting the engine wiring harness electrical connector from the right rear ho2s electrical connector. Before separating the Catalytic Converter from
Exhaust Manifold studs cut its engine harness clip electrical connector clip and remove Catalytic Converter to Exhaust Manifold nuts. Pull the Catalytic Converter hanger out of its position in the hanger bracket. Before installing a new Catalytic Converter remove any needed exhaust seal and extract both ho2s sensors (2 and 3). Before installing the Catalytic Converter with any previous sensors apply gm p/n 12377953 anti-seize compound or equivalent product to the threads. Put the ho2s's (2 and 3) on the Catalytic Converter assembly where you should torque each sensor to 42 n.m (31 lb ft). Insert the new exhaust seal before you guide the Catalytic Converter hanger into its bracket and then install the Catalytic Converter onto Exhaust Manifold studs. Tighten Exhaust Manifold nuts holding the Catalytic Converter in position at 50 n.m (37 lb ft). Reinstall the right rear ho2s electrical connector clip to the engine harness clip then join the engine wiring harness electrical connector with the right rear ho2s electrical connector and slot in the right rear cpa retainer. The right front ho2s electrical connector requires connection to the engine wiring harness electrical connector while you install the right front cpa retainer. Complete the installation by putting the Muffler back in place while also repositioning the transmission crossmember and oil pan skid plate and tighten the two rear pan bolts until they are snug before securing the two front pan bolts if the vehicle has them. Torque these front bolts to 28 n.m (21 lb ft).