I am having the same issue with an '06 Limited! As soon as it hits 50 and shifts it starts making an erratic "wheel bearing" kind of sound. It comes and goes and is always worse when accelerating or holding speed. It goes away when I let off the gas. It also gets worse around a right hand turn, but this also happens at lower speeds (not just 50+). I'm not sure all of these things are related, but it sounds very similar to your issue. I have been thinking possible torque converter issues because I have done all 4 wheel bearings and both front CV shafts. I have not checked the drive shaft yet, but will be soon. I am also dealing with a potential turbo failure (not sure yet) and need to get the timing belt done very soon so funds are tight and I'm already staring down the barrel of like $3000 worth of work. Diagnosing the suspension and all the little noises that I don't like hearing has taken a back seat for now.

I'll be watching very closely here to see if anyone comes up with a solution! Likewise, I'll post here if I find the solution to mine.

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2006 Limited CRD: Frankenlift II, Fumoto Drain Plug, DIY Stage 1 Tune, In-Tank Lift Pump

APC9199 : Thanks for your reply / post.

I have the GDE trans. tune and suspect that I may have a TC issue. I'm going to contact them to get their opinion.

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Marty

'05 CRD, GDE tune(s), JBA stuff, OME, Weeks Stage I & II, "Provent"(custom) +++

*** UPDATE 3 ***

So far all indicators are leaning toward the torque converter. Talked with Florida TC and they pretty much said that's one of the symptoms of a failing TC in a CRD behaves. Especially after eliminating all / many of the other possibilities.

I also searched the forum ...again... and it also confirmed that it very well could be the TC and more than likely IS.

After replacing an axle, front wheel bearing hub, and front driveshaft CV's that probably didn't need to be replaced, I now get to spend MORE $$ on what I finally hope is the offending problem.

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Marty

'05 CRD, GDE tune(s), JBA stuff, OME, Weeks Stage I & II, "Provent"(custom) +++