Bought 4 new Michelin Defenders 195 x 14 not long ago. Maybe 6 months ago. Few weeks ago car started some strange vibrations betwen 40mph - 60 mph. It got worse in time. Tried to pin it down.

Went back to Big-O where I bought the tires to have the balance checked. They said slightly off balance so they re-did all 4. Still vibration, but a bit less.. Went back once again to Big-O. They rotated the tires back to front. Vibration was still there but much less. The manager said they feel the vibration may be due to the "threads" or whatever it is, inside the tires may be "seperating".

Ive never heard of this esp with brand new Michelins. Anyone heard of this? Are the Defenders such a poor design that they would do this? Big-O said if it contiues they will replace the tires, no charge. This was about 3 days ago. Im going back in but just wanted to run this by the Bricksters.

Some comments?. To me, it's so odd that even one tire would do this-but all four??. Actually Big-O thinks its "only" 2 of them, but why take chance? Maybe it was a "bad lot"?? Oh btw I had the alignment checked. Spot on.

Thanks for any input.

'89 240 wagon, A/T, about 300K, looks and runs great!