Update On Strange Shimmy In My '06

[olznut]

I was running around with the tow/haul on today, and noticed when coming to a stop, the transmission shifts down with a rather loud vibration sound from 3-2 I think it is, like something is really out of balance in there, torque convertor shudder or something. Any thoughts? Shift up is fine (love how it locks the convertor early and feel the torque) but shifting down is where the noise comes in, it's really noticeable, and I can make it do it time and time again. Any advice? I kinda don't trust my dealer, unless someone here knows a good diesel tech at a dealer in So Cal... .....