How to Change the Exhaust on a Jeep
- 1). Drive the vehicle onto two automotive ramps and park it so that both front tires are sitting in the middle of the top of each vehicle ramp. Engage the parking brake and place blocks behind the rear wheels before beginning to work. Raise the hood and disconnect the positive cable from the battery and secure it away from its positive post.
- 2). Use a screwdriver to loosen the air tube from the throttle body. Pull the tube free and move it away from the work area. Disconnect the two vacuum tubes that exit the valve cover and keep them with the air tube assembly. Pliers and/or a screwdriver work well together to pull these hoses free.
- 3). Loosen and remove the bolts securing the fuel rail and fuel line. Many bolts in the Jeep are metric, as are these fuel rail bolts. Once the bolts are removed you can adjust the position of the fuel line and rail to a place that is out of the way of the exhaust manifold.
- 4). Disconnect the cables that enter and exit the intake manifold near the throttle body. These cables include the throttle cable and tans pressure cable. Models with cruise control include a cable for that too. Move all the disconnected equipment to the far side of the engine bay. Tie back with plastic tie straps to keep from falling into your work space.
- 5). Remove the protective cover inside the front wheel well that is nearest the exhaust manifold. Without this protector, the wheel well allows access to the header pipe and fasteners. From here you will remove the oxygen sensors that are inserted into the manifold and header pipe. Move the sensors to the far side of the engine bay and continue.
- 6). Disconnect the header pipe from the manifold. Move to the back of the catalytic converter and separate the catalytic converter and header pipe from the rest of the exhaust at the back of the Jeep. Pull the rest of the exhaust out of place by pulling the exhaust hangers free from the old exhaust, then use your reciprocating saw to cut portions of the exhaust apart for easier removal. Never cut or damage the old exhaust hangers as they will be used to hang the new cat-back exhaust.
- 7). Soak the exhaust manifold bolts for at least 20 minutes with penetrating oil. Begin to work the exhaust manifold bolts loose. Loosen the ones that come free easily and then continue to work the hard-to-remove ones with extra oil until they are all free. With all the bolts removed, begin tapping the manifold with a hammer until it breaks free from the engine. Pull the manifold out of the engine bay and clean the surface of the engine where the new manifold will go.
- 8). Install the new exhaust manifold with the gasket sitting between the engine and the manifold. Tighten all the bolts securely using a torque wrench set to 35 foot-pounds of pressure. Apply anti-seize compound on the manifold studs to allow for easy removal in the future. Once the new manifold is installed you can begin to reconnect the header pipe, oxygen sensors, throttle cable, transmission pressure cable, and air tube to their original locations using care to tighten each fitting correctly.
- 9). Hang and connect a new cat-back exhaust system using the original exhaust hangers and the flange that lets it connect to the existing catalytic converter. Run the new tail pipe and position the new muffler in place. Hang the parts using the factory exhaust hangers and tighten together with provided exhaust straps, then secure the exhaust pipe to the catalytic converter flange. With all the pieces together you have changed the exhaust on a Jeep and can expect improved performance and sound from a high-quality exhaust manifold and cat-back exhaust upgrade.
Connect the positive cable to the battery and close the hood. Drive the vehicle off the automotive ramps and test drive the new exhaust system you have installed. Expect to tighten fittings and fasteners again after the test drive to seat all these nuts and bolts securely.