[packman]

My drivetrain has significant NVH at 1300 RPM in all gears, notably 5th (approx. 47 mph). The dealer promptly replaced the exhaust header/shield that audibly "buzzed" at 1300 rpm. The noise is gone but the harmonics (vibration and harshness) are still there. The "buzz" seems to be lessened by adding passengers/weight. Do any of you have insight?

 

[markincc]

My drivetrain has significant NVH at 1300 RPM in all gears, notably 5th (approx. 47 mph). The dealer promptly replaced the exhaust header/shield that audibly "buzzed" at 1300 rpm. The noise is gone but the harmonics (vibration and harshness) are still there. The "buzz" seems to be lessened by adding passengers/weight. Do any of you have insight?

we have this problem too. good luck, harmonic resonance trouble shooting is out of the dealer's league. keep looking for TSBs on this one. It is probably something with rear drive shaft

 

[Cillyone]

Had the same type of problem on a Toyota truck and after months of futzing around it turned out to be belt tension problem, sometimes referred to as belt groan.