Out of balance wheels and tires,
out of round wheels and tires,
bent wheels,
cupped tires,
worn out axles,
sticking U-joints in the driveshaft,
bent wheel hubs,
hot spotted rotors,
dirt/mud/snow in wheels,
All of these things can and do cause vibrations.
Are there more things that can cause a vibration, sure.
But check the simple stuff first.
BTW, a worn inner/outer tie rod or ball joint can expose a shaking in a high speed turn!
