Catalytic Converter: Service and Repair
CATALYTIC CONVERTER 4.7LREMOVAL
WARNING: IF TORCHES ARE USED WHEN WORKING ON THE EXHAUST SYSTEM, DO NOT ALLOW THE FLAME NEAR THE FUEL LINES.
1. Raise and support the vehicle.
2. Saturate the bolts and nuts with heat valve lubricant. Allow 5 minutes for penetration.
3. Remove nuts from the catalytic converter and exhaust pipe flange connection.
4. Loosen exhaust clamp from the catalytic converter and muffler connection.
5. Disconnect oxygen sensor wiring.
6. Heat the catalytic converter to muffler connection with a torch until the metal becomes cherry red.
7. While the metal is still cherry red, twist the catalytic converter back and forth to separate it from the muffler.
INSPECTION
Look at the stainless steel body of the converter, inspect for bulging or other distortion that could be a result of overheating. If the converter has a heat shield attached make sure it is not bent or loose.
If you suspect internal damage to the catalyst, tapping the bottom of the catalyst with a rubber mallet may indicate a damaged core.
INSTALLATION
1. Position the catalytic converter onto the exhaust pipe flange connection. Tighten the nuts to 28 Nm (250 in. lbs.) torque.
2. Install the muffler onto the catalytic converter until the alignment tab is inserted into the alignment slot.
3. Install the exhaust clamp at the muffler and catalytic converter connection. Tighten the clamp nuts to 47 Nm (35 ft. lbs.) torque.
4. Connect oxygen sensor wiring.
5. Lower the vehicle.
6. Start the engine and inspect for exhaust leaks and exhaust system contact with the body panels. Adjust the alignment, if needed.