Disconnect the cable from the negative battery terminal. Loosen the wheel lug nuts on the side of the vehicle from which the exhaust manifold is to be removed, then raise the vehicle and support it securely on jackstands. Disconnect the oxygen sensor electrical connectors. Working under the vehicle, apply penetrating oil to the exhaust Y-pipe-to-manifold (or
Turbocharger) studs and nuts, as they are usually rusty. Remove the nuts holding the exhaust Y-pipe to the exhaust manifolds or turbochargers, and from below, remove the two exhaust Y-pipe-to-manifold nuts. Remove the wheel and the inner fender liner. For 3.5L engines, remove the turbocharger and then remove the two bolts to take off the exhaust manifold heat shield. Remove the manifold mounting nuts and detach the manifold from the
Cylinder Head, noting that the manufacturer recommends removing the exhaust manifold mounting studs from the cylinder heads and installing new studs. Remove the exhaust gaskets and clean the gasket surfaces on the manifold and cylinder heads. Check the exhaust manifold for cracks and ensure all the stud threads are clean and undamaged, as the mating surfaces must be clean before reinstalling the manifolds. Position the exhaust manifold and new gasket over the studs on the cylinder head and install the mounting nuts. When tightening the nuts, tighten the center pair first, then the front pair, and finally the rear pair, to the specified torque. The remaining installation steps are the reverse of removal. Start the engine and check for exhaust leaks.