The replacement process for exhaust manifold pipes installed in 6.0l 6.6l and 8.1l engines starts by elevating and stabilizing the vehicle after which transmission support requires a suitable transmission jack. Begin by removing the transmission mount to transmission support nuts before lifting the transmission off its mount and continuing to dispose of the transmission support crossmember bolts along with the crossmember itself. The replacement process for 6.0l or 8.1l engines includes exhaust
Muffler removal followed by engine harness clip and
Oxygen Sensor pigtail disconnection and then separating the cpa retainer and Oxygen Sensor electrical connector before extracting the Oxygen Sensor. After removing exhaust manifold pipe nuts, users need to shift the transmission slightly downward before completing the exhaust Muffler nut removal step for 6.6l engines and applying the Exhaust Pipe clamp toward the Exhaust Pipe adapter. The exhaust manifold pipe requires removal together with disposal of the utilized seal. New exhaust manifold pipe installation requires water-based lubrication on the hanger bracket for 6.6l engine models. Position the hanger into the bracket while applying a new seal to engines with rpo y91 before installing the exhaust manifold pipe. The exhaust manifold pipe installation requires repeating the lubrication procedure for 6.0l or 8.1l engines with careful alignment of the manifold pipe to the Exhaust Pipe adapter. Secure the Exhaust Pipe clamp at 40 nm torque while the Muffler nuts require 40 nm torque adjustment. When performing work on 6.0l or 8.1l engines you should put on the exhaust manifold pipe nuts then torque them to 50 nm (39 ft. Lbs.). Mount the transmission and apply anti-seize compound gm p/n 12377953 to existing Oxygen Sensor threads. Install the sensor by tightening it to 42 nm (31 ft. Lbs.). The Oxygen Sensor electrical connector and cpa retainer along with the engine harness clip should be reattached if the Exhaust Pipe was not exchanged. For engines with either 6.0l or 8.1l displacement install the exhaust Muffler followed by the transmission support crossmember and its bolts secured at 95 nm (70 ft lbs.). Place the transmission on the support before installing transmission mount support nuts at 40 nm (30 ft. Lbs.) torque and take off the support from the transmission while lowering the vehicle.