Well I don't know whether I would call it tuning, but the vibrations made by driveshafts can be repaired. It usually requires straightening or balancing. The u-joint causes much of the vibrations. They are not replacable in MB shafts but there are a number of top quality driveshaft shops that can do it. The best one I know of is Beyer Motor Works in Mesa Arizona.

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Steve Brotherton
Continental Imports
Gainesville FL
Bosch Master, ASE Master, L1
33 years MB technician