To close the loop on this thread - had a second tire tread separation. Luckily I felt this one and got off the road before the tire came apart. That makes 2 out of the 4 tires with tread separation. We were near the end of a 2,000 mile trip when I started feeling the rocking from this tire.
I had already put 2 new tires on the rear for the trip, and the last two of the originals on the front. I told BFG/Michelin that I didn't ever want to see those tires again, and they gave me 100%, 85%, 50% and 50% credit against the old tires and I bought a full set of a different tire.
Not easy to see, but this is a pic of the bulge. Found it by feel more than sight.
