I never heard of this problem and have not had it happen to my truck but I pulled my silencer ring out almost immediately..

 

I have 03 4X4 47RE and am experencing the same sounds that you have, I have been told the noise comes from chattering torque converter as trans is shifting from 3rd to OD between 45 and 50 MPG under load. With light throttle this does not occur ???

 

gway, one of many in the line of theories. Should have heard the theories that came out of our poker games. After a few home brews you would swear the noise was coming from the left blinker. ;D I can only reiterate that removing the silencer ring definitely took care of mine. Something you may want to consider. It is super easy to remove, 30 minutes tops. Go for a drive and if the noise is still there, put the ring back in, no harm done (although I don't think you will after you hear the nice turbo sound)....and to boot you will know your problem is somewhere else. I think it would be worth it just for the peace of mind whether you leave the ring out or not. I honestly believe you will be surprised. Then there is the fact that just putting up with the noise with hurt nothing, according to DC, if we are talking about the same problem. I have to admit that I was a little skeptical myself at first, then a home brew for courage ;D, and out the silencer ring came. I was elated that had stopped it.

The big question is what does the silencer ring have to do with it? I'm so happy that I don't even care.

Good luck. Let us know how it turns out.

 

I believe the silencer ring is installed by Chrysler in order to lower the turbo noise. If there is back pressure going through the turbo when RPM's drop, the silencer ring does block part of the inlet thus causing vibrations on the turbo blades. I have given my rig hard acceleration just before it shifts into OD just to see if the noise would return. I havn't had any noise no matter how I try. Turbo wine sounds awesome.....