GM 12578647
Heat Shield

First remove the air cleaner outlet duct together with the air cleaner assembly when replacing a 2.9l engine Exhaust Manifold heat shield. According to m30 specifications the transmission filler tube bracket nut needs to be removed from the a.i.r. Adapter until further installation. The heat shield of the Exhaust Manifold needs you to remove first the heated Oxygen Sensor (HO2S) from its position on the Exhaust Manifold after which you detach the three nuts keeping the heat shield on the Exhaust Manifold to finally take off the heat shield. Install the new heat shield to the Exhaust Manifold while using gm p/n 12371386 or canadian p/n 993128 anti-seize on the heat shield nuts. Apply anti-seize gm p/n 12371386 (Canadian P/N 993128) to the heat shield nuts before tightening them to 10 n.m (89 lb in). The procedure requires the ho2s to be reinstalled onto the Exhaust Manifold after the transmission filler tube must be repositioned to the a.i.r. Adapter when this step was conducted. Secure the bracket nut with a torque of 12.5 n.m (111 lb in). Reinstall both the air cleaner assembly followed by the air cleaner outlet duct.

Tighten them to 9 Nm (80 lb in).

Reinstall the air cleaner assembly and the air cleaner outlet duct.

Remove the 5 nuts securing the heat shield to the floor panel and take off the heat shield.

Position the new exhaust muffler heat shield onto the floor panel studs and install the 3 nuts to secure it.

Position the new heat shield onto the exhaust manifold and apply anti-seize GM P/N 12371386 (Canadian P/N 993128) to the heat shield nuts before installing them.

Install the 5 nuts to secure the heat shield to the floor panel, tightening them to 9 Nm (80 lb in).

Lower the vehicle.

First, remove the air cleaner outlet duct and the air cleaner assembly.