2003 Chevrolet Chevy K Silverado Exhaust Popping/Snapping Noise When Vehicle is Hot, at Idle, or Immediately After Vehicle is Shut Off (Replace Muffler Heat Shield) Service Manual

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Follow the service procedure below to correct this condition. Important: Some popping/snapping noise from the exhaust system during cool down is a normal condition. The customer should be made aware that this service procedure is designed to reduce but not eliminate all exhaust system popping and snapping during cool down. 1. Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle in General Information. Caution: 2. Remove the nuts securing the muffler to the catalytic converter. 3. On 6.0L and 8.1L equipped vehicles only, loosen the exhaust pipe clamp. Important: Do not use oil base lubricants on the rubber exhaust hangers. 4. Apply a soapy solution to the exhaust pipe hanger rods in order to ease the removal of the exhaust hangers. 5. Pry the exhaust hangers free from the exhaust pipe hanger rods. Important: It is not necessary to remove the muffler from the vehicle to replace the muffler heat shield. 6. Reposition the muffler to gain access to the muffler heat shield 7. Using an air-powered hack saw blade, or equivalent, cut off the existing muffler heat shield just as the heat shield rises off of the muffler. See the illustration above. 8. Remove the heat shield from the muffler. 9. Hammer flush the remaining heat shield to the muffler. Important: 10. Install the new heat shield (see parts list below) onto the muffler as shown above.