was there any vibration prior to installing the new tires?
I believe the Indy meant lower control arm bushings, the differential is mounted on a rubber mount and I doubt it would cause a vibration.
Front wheel bearings can cause vibration especially if the hub nuts weren't tightened properly.

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'95 E320 Wagon my favorite road car. '99 E300D wolf in sheeps body, '87 300D Sportline suspension, '79 300TD w/ 617.952 engine at 367,750 and counting!