U joints cause vibrations at all speeds. The higher the speed the worse the vibration. It doesn't go away. The vibration seems to be felt under the seats. If you feel it in the steering wheel, check suspension parts. Could still be tires, Like Tom suggested. It could be warped brake rotors. Rotors will get worse when the brakes are applied.
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U joints cause vibrations at all speeds. The higher the speed the worse the vibration. It doesn't go away. The vibration seems to be felt under the seats. If you feel it in the steering wheel, check suspension parts. Could still be tires, Like Tom suggested. It could be warped brake rotors. Rotors will get worse when the brakes are applied.