on saturday i was coming back from port st lucie and out of nowhere the car started shaking like crazy..the thing is it shakes only when im in gear and im accelerating .it does not shake when im just rolling in neutral..we thought it was the back motor mount which we changed yesterday and it still doing it any help??

 

Could be the axle.. Does it by any chance pull to one side?

 

100% axle.

its torque sensitive so it has something to do with transmission area.
ill bet its a bad axle

 

Check the axles, also check that your motor mounts are nice and tight.