Volvo Repair: Vibrating 03 Volvo V70 T5, volvo v70 t5, volvo v70

Question
Hi Enes. About 4 months ago I bought a 03 volvo V70 T5, here in New Zealand. It was imported from Singapore. At that time there was nothing wrong with it (as far as I know). After about a month I started to feel some vibrations in the car. I had the wheels balanced and aligned, but that didn't help. I took it to a garage and was told one of the rear tyres was scalloped, so I had two new rear tyres put on, that didn't help. A dent in the rim was fixed, but that wasn't the problem either. Then they found a broken engine mount, a new one was put on, but it still vibrates!?
It is really bad at higher speeds (120km/h), the steering wheel will shake about an inch from left to right and the whole car shakes. As soon as you let go of the throttle, it stops shaking. What are your thoughts on this? What else could the guys at the garage look at?

Answer
you can have many things wrong it is hard to say what like this thru e-mail  but recommend to you first do tires again it looks you have bad tires or bad drive axle  but first check or replace all 4 tires with good brand from experience that problem shaking at higher speeds is tires most time  other  problems  will be all the time .try 4  tires first