Caution: Wear protective goggles and gloves in order to avoid serious personal injury when removing exhaust parts.

An accumulation of dirt and corrosion may make removing exhaust components difficult. A penetrating oil, used on the threads of the exhaust muffler inlet pipe clamp (U-bolts), can assist in the removal of these components.

Notice: Replacement of exhaust system parts must be OEM standard to ensure that the vehicle operates as designed.

Check for proper alignment when installing a new exhaust pipe/muffler or tail pipe, on any model. Misaligned parts usually cause rattles and noise vibrations in the exhaust system. When aligning the system, leave all nuts/bolts loose, until all parts are aligned. After properly aligning the system, tighten the nuts/bolts, working from the front to the rear of the vehicle. Replace all damaged exhaust system hangers, hanger brackets, and clamps, in order to maintain the exhaust system alignment.

Important: 

1. When servicing the exhaust system requires removing and replacing the oxygen sensor, refer to Heated Oxygen Sensor Replacement in Engine Controls - 3.1L or Heated Oxygen Sensor Replacement in Engine Controls - 3.8L.
2. Apply the GM P/N 9985020 sealer, or equivalent, to all slip-joint connections.
3. Always use new nuts when installing the exhaust pipe to the exhaust manifold.
4. Before installing the new nuts, clean the exhaust manifold stud threads with a wire brush.