Yokohama
Yokohama Geolander and Xtrail problem

I recently bought Yokohama Geolander tyres for my Nissan X-Trail and of recent I am encountering a humming noise coming from the rear of the vehicle whilst driving. In fact, I haven't driven the car for three days incase there is a major problem.
On the 21st August 2013 I took my vehicle in to my mechanic to possibly check the wheel bearings as the humming noise is getting worse!! He cheched the bearings and shocks and said no problem with those things.
He then checked the tyres and tells me that the rear tyres are feathering and wearing unevenly and are definately the problem as to the noise. The front two tyres are fine and wearing evenly.
He went as far as to say 'Get rid of those Yokohamas and buy some good tyres like Michelin'.
as I paid a lot of money for those Yokohamas I wonder if you have a guarantee against this happening to tyres or insurance to replace them. Where do we go from here. I understand that if they were not driven on I would not have had a problem but I have used them and they have given me a problem so how does the guarantee stand?
I tried to send this email to info at Yokohama but it was sent back twice.

Company: Yokohama
Country: South Africa
City: Lanseria

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