2010 Lexus ES 350 Strange bouncing feeling

[EM350]

Hello Everybody.  I have a 2010 Lexus es 350 and when I hit the speed of 75 mph I get a strange feeling in my steering wheel.  It feels like a front wheel is bouncing but, I cant seem to find the problem.  I've replaced the tires with new tires. I have put in new struts and other parts but the bouncing feeling doesn't go away.  The faster I go the more the feeling comes through the steering wheel.  It almost feels like my car is driving on rumble strips.  Please advise if anybody has had this problem.