Removal Procedure

WARNING: This page is about a different car, the 2003 GMC Sierra, 2003 GMC Cab & Chassis Sierra, 2003 Chevrolet Silverado, and 2003 Chevrolet Cab & Chassis Silverado. However, it is still accessible from the selected car via links, so may be relevant.

CAUTION: In order to avoid being burned, do not service the exhaust system while it is still hot. Service the system when it is cool.

CAUTION: Refer to PROTECTIVE GOGGLES & GLOVE CAUTION in Cautions and Notices.

Raise and suitably support the vehicle. Refer to LIFTING AND JACKING THE VEHICLE in General Information.
Support the transmission with a suitable transmission jack.
Remove the transmission mount to transmission support nuts.
Raise the transmission off of the transmission support.

Fig 1: Removing Transmission Mount To Transmission Support Nuts (6.0L, 6.6L & 8.1L)
Courtesy of GENERAL MOTORS CORP.
Remove the transmission support crossmember bolts.
Remove the transmission support crossmember.
If equipped with a 6.0, or 8.1L engine, remove the exhaust muffler. Refer to Muffler Replacement (4.3L, 4.8L, and 5.3L Engines) or Muffler Replacement (6.0L, 6.6L, and 8.1L Engines) .

Fig 2: Removing Transmission Support Crossmember & Bolts (6.0L, 6.6L & 8.1L)
Courtesy of GENERAL MOTORS CORP.
If equipped with a 6.0, or 8.1L engine, perform the following:
1. 8.1 Remove the clip around the engine harness and the oxygen sensor pigtail.
2. 8.2 Disconnect the connector position assurance (CPA) retainer.
3. 8.3 Disconnect the oxygen sensor electrical connector.
4. 8.4 Remove the oxygen sensor.
Fig 3: Removing Engine Harness Clip, CPA Retainer, Oxygen Sensor & Connector (6.0L & 8.1L)
Courtesy of GENERAL MOTORS CORP.
If equipped with a 6.0, or 8.1L engine, remove the exhaust manifold pipe nuts.
Using the transmission jack, lower the transmission slightly.

Fig 4: Removing Exhaust Manifold Pipe Nuts (6.0L & 8.1L)
Courtesy of GENERAL MOTORS CORP.
If equipped with the 6.6L engine, remove the exhaust muffler nuts.

Fig 5: Removing Exhaust Muffler Nuts (6.6L)
Courtesy of GENERAL MOTORS CORP.
If equipped with a 6.6L engine, loosen the exhaust pipe clamp.
Slide the exhaust pipe clamp up onto the exhaust pipe adapter.

Fig 6: Loosening Exhaust Pipe Clamp (6.6L)
Courtesy of GENERAL MOTORS CORP.
If equipped with a 6.0, or 8.1L engine, remove the exhaust manifold pipe.
Slide the exhaust manifold pipe hanger out of the exhaust pipe hanger bracket.
Discard the exhaust manifold pipe seal.

Fig 7: Removing Exhaust Manifold Pipe (6.0L & 8.1L)
Courtesy of GENERAL MOTORS CORP.
If equipped with a 6.0L engine, with regular production option (RPO) Y91, remove the exhaust manifold pipe.
Slide the exhaust manifold pipe hanger out of the exhaust pipe hanger bracket.
Discard the exhaust manifold pipe seal.

Fig 8: Removing Exhaust Manifold Pipe (6.0L w/RPO Y91)
Courtesy of GENERAL MOTORS CORP.
If equipped with a 6.6L engine, remove the exhaust manifold pipe.
Slide the exhaust manifold pipe hanger out of the exhaust pipe hanger bracket.

Fig 9: Removing Exhaust Manifold Pipe (6.6L)
Courtesy of GENERAL MOTORS CORP.