Good Day,
I been hearing this loud growling noise coming from the rear, I would like to say that it started to happen when I put my summer tires on few months ago. At higher speeds it would sound like an airplan is flying over me the faster I go the louder the sound is. I first thought it was my wheel bearing but now I think its a wheel issue because I did perform the 3 and 9 O`clock test on the all wheels and there is no play, Also when I was hearing the noise I would slightly turn right and left to see if the sound gets louder or quieting but the sound remained the same. I know if I go really slow its like I can feel the tires rolling. Yesterday I took a good look at my back tires and this is what I found after doing my research it seems my back tires are scalloping. Attached are some pictures that I took and I think this is the issue, Both back tires have uneven thread on the inner edge of the tires. I remembered 2 years ago I replaced the front ones with Michelin Harmony which they are discontinued now but at the time the back ones did not need replacing. I believe the back ones are original when I got the car in 2008 they are Tiger Paw AWP II. How does Scalloping occur? bad suspension? Car just got an wheel alignment last month so it drives straight now after getting the front tie rods replaced. Should I just buy 4 new tires and try sell the 2 front ones as they are in great shape, if so what do you guys recommend, Are Michelin Defender any good? What do other people here have on their Grand Prix, I would want something that provides the least amount of road noise. I hope new tires will resolve my issue but however im heading on a road trip about 900miles this Friday is having scalloping tires in the back bad to drive on? I would rather buy them in the US as they are cheaper and I will be there anyways.
Thanks
Car is a 2008 Grand Prix Base
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