Avalanche 2500 4WD V8-8.1L VIN G (2003)
8. Remove the clip around the engine harness and the oxygen sensor pigtail.
9. Disconnect the Connector Position Assurance (CPA) retainer.
10. Disconnect the oxygen sensor electrical connector.
11. Remove the oxygen sensor.
12. Remove the exhaust manifold pipe nuts.
13. Using the transmission jack, lower the transmission slightly.
14. Remove the exhaust manifold pipe.
15. Discard the exhaust manifold pipe seal.
Installation Procedure
1. Install a NEW exhaust manifold pipe seal to the exhaust manifold pipe.