On my 84 300sd i came over to Tampa Friday nite and at 65 mph I hit a short stretch of road and it felt like it was driving on a dirt road of washboard. I had to hold on to the steering wheel with both hands. I managed to get to my destination at a reduced speed. I climbed under the car but could not see anything broken. The car did not pull nor make any weird noises. No squeal from the brakes and we just recently has the sway bar repaired where it broke from the front. I have no tools with me and I assume I can drive the car back home (125 miles) at a reduced rate of speed. I am just trying to figure what should be replaced on the front end. The car has 250,000 and new tires so I know it is not an unbalanced situation. Any help will be appreciated.