Installation Procedure

Install the rear exhaust hanger brackets to the rear exhaust hangers.
NOTE: Refer to FASTENER NOTICE
Install the 2 nuts securing the rear exhaust hangers to the rear exhaust hanger brackets.
Tighten

Tighten the rear exhaust hanger nuts to 30 N.m (22 lb ft).

Fig 1: Rear Exhaust Hanger Brackets & Hangers
Courtesy of GENERAL MOTORS CORP.

NOTE: When inspecting or replacing exhaust system components, make sure there is adequate clearance from all points on the underbody to prevent overheating of the floor pan and possible damage to the passenger compartment insulation and trim materials.
Place a NEW catalytic converter gasket over the catalytic converter studs.
NOTE: Refer to FLEX DECOUPLER NOTICE .
With the aid of an assistant, raise the exhaust system into position, aligning the catalytic converter with the rear exhaust manifold pipe.
Finger tighten the 4 nuts to the catalytic converter studs.

Fig 2: Catalytic Converter
Courtesy of GENERAL MOTORS CORP.
Install the 2 bolts securing the rear exhaust hanger brackets to the rear compartment rails.
Tighten

Tighten the rear exhaust hanger bolts to 50 N.m (37 lb ft).

Fig 3: Rear Exhaust Hanger Brackets to Rear Compartment Rails Bolts
Courtesy of GENERAL MOTORS CORP.
Install the 2 bolts securing the center exhaust hangers to the rear suspension support brackets.
Tighten

Tighten the center exhaust hanger bolts to 30 N.m (22 lb ft).
Tighten the 4 catalytic converter nuts previously installed in step 5.
Tighten

Tighten the catalytic converter nuts to 25 N.m (18 lb ft).
Install the heated oxygen sensor. Refer to HEATED OXYGEN SENSOR (HO2S) REPLACEMENT BANK 1 SENSOR 2 .
Remove the oxygen sensor wiring harness heat shield. Refer to Oxygen Sensor Wiring Harness Heat Shield Replacement .
Lower the vehicle.

Fig 4: Center Exhaust Hangers to Rear Suspension Support Bracket Bolts
Courtesy of GENERAL MOTORS CORP.