How to Change the Catalytic Converter on a Chevy Silveradoby Chris Moore
The catalytic converter regulates and reduces pollutants within the vehicle's exhaust. Vehicles are required by law to have them, so you need to replace them if they are no longer working. On a current Chevy Silverado, the catalytic converters are welded to the front exhaust pipe assembly, so replacing a catalytic converter means replacing the entire front exhaust pipe assembly. This process can differ on older models (specifically ones made prior to 2007), so check with your mechanic.
Raise the truck and support it on jack stands.
Disconnect the electrical connectors for the converter's upstream and downstream oxygen sensors. Unscrew and remove the sensors using an oxygen sensor socket.
Unscrew and remove the three nuts that are on the upper-left and right flanges connecting the front exhaust pipe assembly to the exhaust manifold's flanges using a wrench. Remove the nuts for the rear flange of the front exhaust and remove the front exhaust pipe.
Install new flange gaskets onto the three mounting flanges of the replacement exhaust pipe (which will include the replacement converters).
Coat the threads on the mounting nuts and bolts with anti-seize compound. This includes the threads on the oxygen sensors.
Install the exhaust pipe system and securely tighten the nuts and bolts for the three flanges connecting it to the manifold and the rest of the exhaust system.
Connect the upstream and downstream oxygen sensors to the front exhaust pipe using the same socket as before.
- It may be much cheaper to have a catalytic converter professionally replaced, as they are required by law to have an extended warranty.
Items you will need
- Floor jack
- Jack stands
- Socket wrench
- Oxygen sensor socket
- Chevy Silverado front exhaust pipe assembly
- Anti-seize compound
- Small brush
- "Chilton General Motors Full Size Trucks Repair Manual"; Mike Stubblefield; Haynes North America; 2009
- exhaust fulmes image by bilderbox from Fotolia.com