Chevrolet Impala Engine Vibration

I Bought The Car Used. I Am Feeling Vibration At 65 To 70 Mph Not In Steering Wheel, But In The Car. I Had The Tires Balanced No Change. I...

Horrible Vibration In Car Whenever I Get Over 15mph. Kind Of Scary/annoying Over 30mph.

Runs Smooth While Driving But When Holding Still It Has A Rocking Feel To The Car Not As If Its Reving Up But Like Something May Be Loose.

I Have A Vibration In The Rear Of The Car That Is Non-existant On A Straightaway; Yet In A Left Turn There Is A Significant Vibration. I...

:( Alright. First, It Is A 2000 Hyundai Accent, 26000 Miles. Clean Air Filter, Changed Fuel Filter Last September, Cleaned Fuel System Last...