Honda Civic vibrates to assault

Hello everyone, first I want to apologize for the extensive of this post, but I need collaboration ... and for this purpose I need to explain well. Honda Civic 2004 Automatic 170000 km, an owner, the car is in very good condition, without blows, it shows that they have taken care of it ... this chub as they say here I inherited from a very good friend, in fact I am the room that tries to fix it. The car vibrates when accelerating, at 100kmh, if you step thoroughly on flat terrain vibrates quite strong, if you go up at the same speed the symptom increases as if it entered resonance, very strong, I scared the first time it happened to me trying it. It is as if all the passee (motor-box) move from side to side, it always begins, but when the entire self is accentuated ... it does it more between 80 and 120, if you release the pedal of the asceler the car the car is instructed instantly, it remains as yield ... zero vibration ... it has changed, for other people, but I verify everything when you take this church: Silenblock of the suspension, the 4 shock absorbers, etc, etc. everything for me is correctly installed. I verify the car in the alignment service and has no game anywhere, the address angles, all ok. My friend before 4 tires of the same car was achieved (without any symptoms), nothing the same ... the palieres or semi-piles changed, either ... then trying it, notic He feels even being the lifted car, noticed that the right wheel did not turn (short shovel) and the left (long shore), verify that it would not be slow A loud noise (like a shock of Piñoñes) inside the box, right in the place where the differential is riding ... the box is an automatic that I know (Slxa, changes some clutches burned to one some time ago). The box works correctly, does not skate, all ok, the electronic system does not yield anything ... I need advice or help, I do not know what to do, if I repair the box (for me the gap of the differential of this, the vibrations and noises are the unique abnormal that I have been able to detect as a failure), and then it is the same ... Can a defect of the differential dwell the symptoms?, Is something happening to me? Do I tell the person to sell it, like 2 previous colleagues? Hehehe ... Forgive the extensive, any opinion will be well received, I am trying to be objective, but I still think "cursed auto" .... Greetings to all.

Hello I had a similar problem with a Honda Civic Standar and it turned out that a dice was not complete then in high revolutions vibrated, greetings