Installation Procedure
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- Install a NEW exhaust manifold pipe seal to the exhaust manifold pipe.
- Install the exhaust manifold pipe.
- Using the transmission jack, raise the transmission.
- Install the exhaust manifold pipe nuts.NOTE: Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems.
Tighten
Tighten the nuts to 50 N.m (39 lb ft).
- If the old oxygen sensor is being reused, apply anti-seize compound GM P/N 12377953 or equivalent to the threads.
- Install the oxygen sensor.
Tighten
Tighten the sensor to 42 N.m (31 lb ft).
- Connect the oxygen sensor electrical connector.
- Connect the CPA retainer.
- Install the clip around the engine harness and the oxygen sensor pigtail.
- Install the exhaust muffler. Refer to MUFFLER REPLACEMENT (4.8L AND 5.3L ENGINES) or MUFFLER REPLACEMENT (6.0L AND 8.1L ENGINES) .
- Install the transmission support crossmember.
- Install the transmission support crossmember bolts.
Tighten
Tighten the bolts to 95 N.m (70 lb ft).
- Lower the transmission onto the transmission support.
- Install the transmission mount to transmission support nuts.
Tighten
Tighten the nuts to 40 N.m (30 lb ft).
- Remove the transmission jack.
- Lower the vehicle.