Underbody Exhaust Rattle - keywords 6.0 body bump catalytic converter floot heat LQ4 pan pipe shield tinny

The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI.

Some customers may comment on an underbody rattle noise that emanates from the exhaust system on a 1500HD pickup with an LQ4 engine. Root cause appears to be contact between the exhaust catalytic converter and the floor pan heat shield.

For service, bias (bend) the heat shield to prevent contact with catalytic converter.

Please follow this diagnostic or repair 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.