On our way to another show we went over a set of railroad tracks. I thought I was going over the tracks at a slow speed. I guess not, we hit it hard and the tire developed a “bubble”. At least at the time it looked like a bubble.
What it really turned out to be was the tire coming out of the lip of the rim a bit. Not enough to lose air but definitely deforming the sidewall.
I took it to the local tire repair shop again.
The 255/30/22 size is like a freakin’ rubber band on the rim. I had it replaced with the same size since it was readily available. I will be changing the tire dimensions in the near future to 245/35/22. This will give a little more sidewall between the rim and asphalt.