So now I have a new problem with the dually. Up around 55-65 under light or medium acceleration the whole truck shudders badly, seems to be coming more from the rear. However at 1/2 or more go pedal nothing. I am really confused because it stops as soon as I take my foot out of it. Cruise control seems unaffected.
I am going to check the leaf springs and the rear tires along with the transmission mount. Is there anything else I might look at?

 

Hanger bearing.

 

Hanger bearing?

 

The hanger or carrier bearing for the center point of the driveshaft. I was going to guess a bad U-Joint as possible.

 

I was thinking carrier is what he was thinking. However I have a single piece drive shaft so no carrier bearing lol

 

Do'h..

Well is it high frequency buzz or more low frequency? Might also be a separating tire.

 

Low frequency, almost feels like axle hop as weird as it sounds.