Catalytic Converter: Service and Repair
Catalytic Converter - 5.4LSpecial Tool(s):
Material:
Removal and Installation
WARNING: The normal operating temperature of the exhaust system is very high. Never attempt to service any part of the system until it has cooled. Be especially careful when working around the catalytic converter. The temperature of the catalytic converter rises to a high level after only a few minutes of engine operation. Failure to follow these instructions may result in personal injury.
CAUTION: Do not use oil- or grease-based lubricants on the isolators. These lubricants may cause deterioration of the rubber. This can lead to separation of the isolator from the exhaust hanger bracket during vehicle operation.
NOTE: Exhaust fasteners are of a prevailing torque design. Use only new fasteners with the same part number as the original. Torque values must be used as specified during reassembly to make sure of correct retention of exhaust components.
1. With the vehicle in NEUTRAL, position it on a hoist. For additional information, refer to Maintenance/Service and Repair.
2. Disconnect the battery ground cable. For additional information, refer to Battery.
3. Support the muffler and tailpipe assembly and exhaust intermediate pipe with a safety stand.
4. Release the exhaust intermediate pipe and (if equipped, the extension pipe) and the front muffler and tailpipe hanger isolators.
5. Loosen the exhaust intermediate pipe-to-catalytic converter Torca clamp nut and release the tension on the clamp.
^ To install, tighten to 40 Nm (30 ft. lbs.).
6. Remove the exhaust intermediate pipe and (if equipped, the extension pipe) and the muffler and tailpipe from the catalytic converter.
7. Disconnect the heated oxygen sensors and the catalyst monitor sensor electrical connectors.
8. NOTE: LH shown, RH similar.
Remove the 2 LH and 1 RH heat shield-to-crossmember bolts.
^ To install, tighten to 10 Nm (89 inch lbs.).
9. Remove the 2 crossmember-to-rear transmission mount nuts.
^ To install, tighten to 95 Nm (70 ft. lbs.).
10. Support the rear of the transmission with a safety stand.
11. NOTE: RH shown, LH similar.
Remove the RH and LH transmission crossmember-to-frame nuts and bolts and remove the transmission crossmember.
^ To install, tighten to 81 Nm (60 ft. lbs.).
12. Remove the 4 catalytic converter-to-exhaust manifold nuts and discard. Remove the catalytic converter.
^ To install, tighten to 40 Nm (30 ft. lbs.).
13. If installing new catalytic converters, remove the heated oxygen sensors (HO2S) and the catalyst monitor sensors.
^ Apply a light coat of high temperature nickel anti-seize lubricant to the HO2S and catalyst monitor sensor threads prior to installation.
^ To install, tighten to 46 Nm (34 ft. lbs.).
14. To install, reverse the removal procedure.