Has anyone else have trouble with these tires? I purchased them in June of 07 from the tirerack for my garage queen. They have 8/32 of tread left on them. The first one had tread seperation of about a foot in June and now a second one has about 6 inches of tread missing. Both had the missing tread from the inner most tread block. Both were on the rear wheels when the seperation occured. Even tread wear on both tires. Both still held air.

When the first one happened, no local Bridgestone dealer would honor the Bridgestone 7 year tread seperation warranty as the purchase was from tirerack. I had to ship the tire back to tirerack and get a replacement. Now the 960's are discontinued. Was it due to this issue?
Do I have to worry about the other 2 tires? Can I mix the 970's(the 960's replacement) with the other 3 960's?

 

The RE960 was a very successful tire for Bridgestone and has had no issues with tread separation. The RE970 is a new and improved version of the RE960 and can be mixed in axle pairs unless the vehicle is AWD. So, you need 2 RE970's to mix with your 2 best RE960's if this is a 2WD otherwise it's 4 tires. The tread warranty on workmanship for that tire is 5 years for date of purchase not 7 and any authorized Bridgestone dealer would honor the warranty just as The Tire Rack does. It may be the local tire shops you visited were not Bridgestone dealers? This network of Bridgestone dealers is in place because often if you have a damaged tire you may not always be able to go back to exactly the shop you bought the tires from for example if you are traveling or have moved to another city.

 

They actually had pulled a 960 out from stock and had it on the floor when they asked me where I purchased the tire. When I said TIrerack they put the tire back and said they could not help me but they would say the tire was under warranty since it still held air.

 

If they are truly a Bridgestone Dealer, call Bridgestone and report them...

Also, I would suspect you have a tire wear issue that is causing the tires to come apart... Any pictures?

 

Should there be some glue that holds the tread down? The surface seems too smooth.

 

Man, in all my years, have never seen a large chunk like that just separate from the body... could have been because of a heat issue, or all sorts of other issues... odd, to say the least...

Tires are not glued together, instead they are vulcanized.... the layers are assembled, then the tire goes into a mold in which a bladder is inflated inside the tire with extremely hot water/ steam...

 

This second time it was 6 inches long. The first was 12 in.

 

On a somewhat related note, I got a set of the 970s a few months ago and they are wonderful. A whole lot quieter than the stock dunlops, and performance in rain is great. A few days after I got them, I was able to comfortably go 65+ on the highway with standing water on the road. Even at highway speeds, there is very little road noise. They were a bit more pricey than other tires, but I have been very pleased with them.

 

Overheated. Tire was driven on underinflated too long or saw some track/autocross use it was not intended for. As Mitsuguy stated no glue, rubber is heated to bond layers, the only way to break that bond is to heat up to the bonding temperature once again.

The fresh wear on that outside shoulder, indicates underinflated. The outside shoulder rubber is deep black which is fresh wear also the extreme outside shoulder is much, much more worn than the center of the tire. These were underinflated for awhile.

 

Could also be camber / toe causing it to heat up quite a bit...???