Get the car up in the air and spin the wheels looking for a bent wheel. When the wheel is bent, it will only feel f-ed up at certain speeds (my guess is that you have a bent wheel or two). I had a '71 bug that shook at a 70mph VERY bad and then after 75mph was fine, 4 bent wheels. Then look closely at the tire tread, stand back if you need to ( you are looking for tread that isn't straight like it should be, spin the tire and watch). If the tires are worn or worn uneven, replace them anyway. After you check all that, you can look at your shocks.

Your tranny is toast.

 

how do you figure my tranny is toast. I also need an alignment. woudlnt this have something to do with my viabration,