I have a 14 plate Fiesta and it had really harsh vibration with severe road noise. So i took it to my local dealer and turned out it had a slightly buckled wheel. So got a new wheel fitted and it still vibrated. Checked wheel balancing, checked wheel alignment, checked all suspension and steering - all 100%. Though still vibrated. Checked tyre pressures all round. Still vibrated.

Car had 4800miles on it and Ford decided to check tyre tread for possible uneven wear. Was well legal at front and virtually new on the back, but none the less they diagonally swapped the wheels (swapped front right and back left, and swapped front left and back right)...drove up the road and it was perfect.

Turns out with the tread had worn unevenly and there was an imbalanced in the tyre whilst in motion carrying the weight of thw car. But as a tyre on a wheel on a balancer it was balancing up fine.

Worth a punt mate incase thats your problem!