Moan Or Vibration At 2200-2600 RPM While Driving - keywords 2.4L 3.5L body bracket buzz driving exhaust felt floor hanger hum LE5 LZ4 MPH pan pipe shifter

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

The complaint/condition is a moan and or vibration at 2200-2600 RPM while driving at approximately 65 MPH. The vibration is mainly felt in the body structure of the vehicle especially through the console shifter assembly and is RPM related, not road speed related.

To address this condition the following changes to the exhaust system need to be made:

1. With the vehicle on the hoist, stand at the rear of the vehicle and look forward. You need to make sure the exhaust is parallel to the body of the vehicle (NOT Twisted down left or right). If the exhaust is twisted then the exhaust needs to be loosened at the catalytic converter. You need to twist the exhaust in the opposite direction to release the tension on the center exhaust isolators.

Some suggestion on how to get more adjustment if needed:

•	Loosen up the catalytic converter bolts.

•	The LH/RH rear muffler hanger on the vehicle body may need to be adjusted vertically upward (approx 8-10 mm).

•	The LH/RH center exhaust hanger on the body may need to be adjusted slightly vertically downward (approx 5 mm).

2. After the exhaust is properly centered, then replace both LH/RH center exhaust hanger isolators with P/N 25868133.

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.