Disconnect the cable from the negative battery terminal. Disconnect the electrical connectors from the oxygen sensor and the catalytic converter monitor. Raise the front of the vehicle and support it securely on jackstands; on 2013 and later models, remove the lower engine splash shield and skid plate if equipped. From below, disconnect the crossover pipe. Remove the heat shield over the front exhaust manifold and the six nuts securing the exhaust manifold, then remove and discard the manifold gasket and the six nuts. Remove the exhaust manifold and, using a stud holding tool or a pair of nuts tightened together over a stud, extract the exhaust manifold studs and discard them. Use a scraper to remove all old gasket material and carbon deposits from the manifold and
Cylinder Head mating surfaces, checking the manifold for warpage and resurfacing if necessary, while being cautious not to gouge the aluminum engine parts. Install new exhaust manifold studs with light oil on the threads, then place a new manifold gasket over the studs, followed by the manifold and new self-locking nuts. Tighten the nuts, starting with the center fasteners and working towards the ends, to the specified torque. For the rear exhaust manifold, disconnect the cable from the negative battery terminal, remove the EGR pipe from the exhaust manifold on 3.0L engines, and disconnect the connector to the rear bank oxygen sensor. On 3.5L engines, remove the rear-bank catalytic converter, noting that the converter heat shield on 3.0L AWD models requires the removal of the steering gear heat shield first. Remove the nuts from the exhaust manifold flange and separate the crossover pipe from the manifold, then remove the six exhaust manifold mounting nuts and the manifold from the engine, discarding the manifold gasket. Extract the exhaust manifold studs and discard them, then scrape all gasket material and carbon deposits from the mating surfaces, checking for warpage and resurfacing if necessary. Install new exhaust manifold studs with light oil on the threads, place a new manifold gasket over the studs, install the manifold and new self-locking nuts, and tighten the nuts starting with the center fasteners and working towards the ends to the specified torque. The remainder of the installation follows the reverse order of removal.