Hi guys, I need some help plzzzzz....... The problem I'm having is my steering wheel shakes very very bad only when I apply brakes at 60 miles and above, but under 59 miles they don't.

So I have to tap on the brakes to drop the speed to below 59 miles in order to press and hold on to the brakes. On normal driving the steering wheel is just fine.
I did check my front brakes and they are just fine. Any idea what could cause this problem?
thanks guys
