Problem with my 2005 Liberty shaking

I have a 2005 Liberty Renegade, it has 84,400 miles, my car started shaking when I started braking to come to a stop. I was told it was my tie rod, so I replaced it, my car was still shaking after this, I was then told it needed an alignment.. Went to have this done, and was told my problem with is in the drive train or shaft. What my car does is shake violently if I go over 30 mph and when I start to hit under 20 mph and braking...

Has anyone ever had this problem, or know what this could be? :screwy:

Had a similiar problem with an older Cherokee, check the front u-joints behind the wheels. My right side was bad and would shutter terrible in a left turn over 40mph. On a straight run, at about 40, would have a real bad shimmy that would go straight through the steering wheel.