Silverado 1500 2WD V6-4.3L (2007)
Exhaust Pipe: Customer Interest
Exhaust System - Underbody Rattle/Clunk/Rumble Noise
Bulletin No.: 07-06-05-003
Date: March 08, 2007
TECHNICAL
Subject:
Exhaust Pipe / Muffler Rumble, Rattle, Moan, Drone, Vibration Noise (Align Exhaust and Install New Exhaust Seals)
Models:
2007 Chevrolet Silverado 1500 Series Only
2007 GMC Sierra 1500 Series Only
Condition
Some customers may comment on an underbody rattle/clunk/rumble noise.
Cause
This condition may be due to insufficient clearance between the exhaust and transmission crossmember.
Correction
Measure the clearance between the exhaust pipe and the transmission crossmember.
If the clearance is between 15 mm-30 mm (0.59 in-1.18 in), this is not the cause of the customer's concern. Do not proceed with this bulletin. Continue to
diagnose the customer's concern.
If the clearance is less than 15 mm (0.59 in), realign the exhaust following steps 2-6. Disconnect the Y-pipe outlet from the exhaust muffler assembly.
Loosen both the left and right exhaust manifold pipe nuts. It may be necessary to remove the right side 02 sensor to gain access to all the right side
exhaust manifold nuts.
The left exhaust MUST be torqued first.
Tighten the left exhaust manifold pipe bolts in the sequence indicated in illustration "A" above.
Tighten:
Tighten the bolts to 50 N.m (37 lb ft).
Monitor the clearance between the exhaust pipe and the transmission crossmember. It may be necessary to push up on the exhaust while tightening the
right exhaust manifold nuts in order to achieve a minimum clearance of 15 mm (0.59 in).
