Three-Way Catalytic Converter Replacement

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Fig 1: Three-Way Catalytic Converter Components

Courtesy of GENERAL MOTORS COMPANY

Callout	Component Name
Preliminary Procedure Remove the engine skid plate (if equipped). Refer to Oil Pan Skid Plate Replacement (1500 with RPO NZZ) , Oil Pan Skid Plate Replacement (2500/3500 with RPO NZZ) Remove the transmission support crossmember. Refer to Transmission Support Crossmember Replacement (4WD 2500 Series) , Transmission Support Crossmember Replacement (4WD 1500 Series) , Transmission Support Crossmember Replacement (2WD 2500 Series) , Transmission Support Crossmember Replacement (2WD 1500 Series) Disconnect the oxygen sensors. Refer to Heated Oxygen Sensor Replacement - Bank 1 Sensor 1 (1500 Series) , Heated Oxygen Sensor Replacement - Bank 1 Sensor 1 (2500 Series) ,, Heated Oxygen Sensor Replacement - Bank 1 Sensor 2 (1500 Series) , Heated Oxygen Sensor Replacement - Bank 1 Sensor 2 (2500 Series) ,, Heated Oxygen Sensor Replacement - Bank 2 Sensor 1 (1500 Series) , Heated Oxygen Sensor Replacement - Bank 2 Sensor 1 (2500 Series) , and Heated Oxygen Sensor Replacement - Bank 2 Sensor 2 (1500 Series) , Heated Oxygen Sensor Replacement - Bank 2 Sensor 2 (2500 Series) .
1	Left Exhaust Manifold Nut (Qty: 3) WARNING: Refer to Exhaust Service Warning . WARNING: Refer to Hot Exhaust System Warning . CAUTION: Refer to Fastener Caution . Tighten 50 N.m (37 lb ft)
2	Seal
3	Right Exhaust Manifold Nut (Qty: 3) Tighten 50 N.m (37 lb ft)
4	Seal
5	Muffler Clamp Nut TIP: Replace the exhaust muffler clamp with a NEW clamp. Tighten 28 (21 lb ft)