GM 12580260
Exhaust Manifold, Passenger Side

The right side Exhaust Manifold replacement process (RPO LY7) requires air inlet duct and master cylinder fluid level sensor removal so that you can lower the powertrain adequately. You must start by taking off the engine mount struts followed by lifting the vehicle to its maximum height. The procedure requires a long extension to release the Catalytic Converter for access to the exhaust crossover pipe nuts. Deal with the exhaust crossover pipe by removing both right bank Exhaust Manifold nuts and Exhaust Manifold bolts before removing the Exhaust Manifold which requires discarding the gasket. The first step to install a new Exhaust Manifold requires users to remove the heat shield bolts, separate the heat shield before cleaning both sealing surfaces. To install the heat shield position it above the Exhaust Manifold before screwing bolts down to 10 n.m (89 lb in). The bolt passes through the Exhaust Manifold hole before you place a new gasket and correctly position the manifold next to the Cylinder Head until the bolt reaches a proper tension. Screw in all remaining Exhaust Manifold bolts until they achieve 20 n.m (15 lb ft) of torque while crossover exhaust pipe nuts require a torque setting of 34 n.m (25 lb ft). First reconnect the Catalytic Converter before you link the intermediate Steering Shaft to the steering gear then lower the vehicle and lastly replace the engine mount struts master cylinder fluid level sensor and air inlet duct.

Detach the two bolts that connect the exhaust crossover to the left exhaust manifold.

Tighten them to 34 N.m (25 lb ft).

Install one exhaust manifold bolt through a bolt hole in the manifold, then place a new exhaust manifold gasket onto the bolt and position the manifold against the cylinder head.

Position the exhaust manifold heat shield to the manifold and install the heat shield bolts, tightening them to 10 N.m (89 lb in).