01-05 Chevrolet Silverado/GMC Sierra C/K2500HD C/K3500 with 6.0 and 8.1 Gas Engines Exhaust Buzz or Rattle Noise - kw GMT800 LQ4 L18 cold start up

The following diagnosis might be helpful if the vehicle exhibits the symptom described in the PI.

Owners my comment on a buzz or rattle noise at 1200 to 1800 RPMs under light loads or on a cold start. The noise maybe be coming from the muffler heat shield.

To correct this concern install a strap, part number 10391259, over the middle of the muffler and heat shield. This strap will help secure the heat shield and eliminate the noise.

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Please follow this diagnosis process thoroughly and complete each step. If the condition exhibited is resolved without completing every step, the remaining steps do not need to be performed. If these steps do not resolve the condition, please contact GM TAC for further diagnostic assistance.

(01-05 Chevrolet Silverado C/K2500HD C/K3500 with Gas Engines) and (01-05 GMC Sierra C/K2500HD C/K3500 with Gas Engine)

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