GM 88890560
Exhaust Manifold

Beginning the Exhaust Manifold replacement starts with removing the air cleaner resonator outlet duct followed by unstowing the transmission filler tube stud nut from the a.i.r. Adapter and shifting the filler tube to the side. Start by taking out both the Exhaust Manifold's oil level indicator tube and Oxygen Sensor from their respective places. Heat shield nuts from the 4 manifold need removal and the shield itself must be taken off. Raising the vehicle enables workers to remove Exhaust Pipe bolts from the Exhaust Manifold which should be followed by lowering the vehicle. Remove the Exhaust Manifold bolts then gradually pull out the Exhaust Manifold together with its accompanying gasket. Installation requires new Exhaust Manifold gaskets that need to be installed alongside the Exhaust Manifold. Threadlock gm p/n 12345493 (Canadian P/N 10953488) must be applied to all manifold bolts and the correct order must be followed to tighten them to 25 nm (18 ft. Lbs.) for the first, second, and final passes. Install the Exhaust Manifold heat shield studs by hand tightening them to 10 nm (89 inch lbs.). The installation process requires the fitting of an Oxygen Sensor along with an Exhaust Manifold heat shield to which you should apply anti-seize compound gm p/n 12371386 onto the heat shield nuts before tightening them to 5 nm (44 inch lbs.). After raising the vehicle reinstall the Exhaust Pipe onto the manifold while using a seal and bolt it down using nuts that need tightening to 50 nm (37 ft. Lbs.). Lift the vehicle to replace the transmission tube and place the a.i.r. Adapter block stud then fasten a nut before torque it to 10 nm (89 inch lbs.). Install the air cleaner resonator outlet duct as the last step.

Lower the vehicle and then remove the manifold heat shield.

Raise the vehicle again, connect the exhaust pipe to the manifold with a seal, and tighten the nuts to 50 Nm (37 ft. lbs.).

Reposition the transmission filler tube onto the A.I.R. adapter block stud, securing it with a nut tightened to 10 Nm (89 inch lbs.), and finish by installing the air cleaner resonator outlet duct.