OEM 2003 GMC Envoy Exhaust Manifold

2003 GMC Envoy Parts Questions & Experts Answers

• Q: How to replace the exhaust manifold on a 4.2L engine on 2003 GMC Envoy?

  A: One must begin the 4.2l Exhaust Manifold replacement process by removing the air cleaner resonator outlet duct before disconnecting the transmission filler tube stud nut that attaches to the a.i.r. Adapter while moving the filler tube to a safe position. Begin the replacement procedure by taking away both the oil level indicator tube along with the Exhaust Manifold Oxygen Sensor. Separate the four heat shield nuts from the manifold then detach its heat shield. Lift the vehicle in order to loosen the Exhaust Pipe bolts attached to the Exhaust Manifold before lowering it. Use a tool to remove the Exhaust Manifold bolts and extract both the Exhaust Manifold with its gasket. Professional installers should use new Exhaust Manifold gaskets before fitting the Exhaust Manifold into position. The technician should apply threadlock gm p/n 12345493 (Canadian P/N 10953488) on manifold bolts before installation with a final tightening sequence to 20 nm (15 ft. Lbs.) for three passes. Attach Exhaust Manifold heat shield studs to their position while tightening them to 10 nm (89 inch lbs.). After putting the Oxygen Sensor back into place you must install the Exhaust Manifold heat shield while applying gm p/n 12371386 anti-seize compound to heat shield nuts before tightening them to 5 nm (44 inch lbs.). Raise the vehicle to install the Exhaust Pipe to the manifold through a sealing process before securing it with nuts set to 50 nm (37 ft. Lbs.). Afterward, lower the vehicle down. You must complete the process by securing an oil level indicator tube before positioning transmission filler tube into place on a.i.r. Adapter block stud while tightening the nut to 10 nm (89 inch lbs.) and ending with air cleaner resonator outlet duct installation.