Bridgestone B391?s - A Dent{P}
Bridgestone B391?s on Almera 1.8

I have just replaced a set of these (4 years old and 27K) because one of them had a crevasse at the edge of the steel belts. I had the wheels off to change the brake fluid and checked the tyres over as you do. This one was at the 2 mm marker and I was toying with the idea of leaving them on for another month or two until I found this. It was about 1-1/2? in from the side wall, ¾? long and looked like a deep void rather than foreign object damage. The opening was also elliptical. I had been happily doing 70 MPH with this tyre!. Next trip was to the tyre shop and have now shod it with Dunlop SP30?s all round.

I not suggesting this is a common fault, but I?d advise checking B391?s when they are well worn.
Happy motoring.