Wheel balance
i would really like to know myself
Tire out of balance, tire defect, bent wheel, defective wheel bearing, loose lug nuts, or worn suspension or steering parts.
If it happens when you are driving fast (60-70 MPH) it could be that your wheels are out of alignment.
a shake in the steering wheel could be a few things,a bad rim,broking belt in one of front tires,aliment,ball joints,or could be all of these thing Could be as simple as wheel balance but have the front end checked by a mechanic to be safe.
have your front tires rebalanced.
Check the wheel balance
More than likely you have a tire out of balance. It is possible you have a bent wheel. Have your tires balanced, inspected, and rotated.
It might be your transmition...
One or more tire out of balance, a bent wheel, or defect in a tire.
Most common reason is improperly balanced wheels, next would be alignment but that usually causes a pull to the left or right.
Tire out of balance, bent wheel, loose or worn suspension parts. More than likely balancing & rotating your tires will correct this.