Vibration crazy when driven from 70 to 80 KM/hour and quieter at 90 KM/hour.

Tire belt separation would be my guess, move your hand over the tread around the tire and feel for any difference in the evenness of the tread.

It sounds like it needs a wheel alignment and ballance,also check for tyre out of shape.i.e. bubble in the tyre,or tyre worn through.

Tires.Agree with Profg. 90KPH isn't really fast enough for a balance issue to show up.Flat spots or other defect. Be sure rims aren't bent.

Check your lower ball joint too I have experience this trouble I thought it was the strut shock and tie rods And then I install new tires and did alignment still vibrate on me going 70kmh

Bad tires .........