Faulty shocks causing tyre damage

We dealt with Kingsmead Toyota regarding a loud humming noise coming from the tyres. This was reported during various services but we were constantly told that the problem was with the tyres and not the shocks We had changed tyres based on their advice and still the problem continued. This was reported to Toyota again and again they claim that it's the tyres and not the shocks. We then had the shocks tested at HiQ and the test showed that the shocks needed replacing. Toyota claim that they don't replace shocks unless they are leaking oil. Toyota still refused to replace the shocks despite the damage it was causing. These faulty shocks were causing a problem very early after purcahse of the vehicle.