If the vibration is during acceleration (load) and goes away when you let gas pedal then you can look at the driveline components, but if it is at certain speeds and especially if you feel the vibration in the steering wheel then look at the front wheels alignment and balance. Also for the back wheels check the balance of the drive axels, by suspending the car and running it at the speed where the vibration occurs, loose CV joints also can cause vibrations.
I hope this helps.