A few days ago I replaced my PR4 GT front tire in ambient temperature of 45 F. (BTW, I got 13,000 miles out of it) I replaced it with a Bridgestone T30 GT. I know from experience it is hard to mount the GT type tires and also hard to mount any tire when it is cold out. I warmed up the new tire by storing it in the house and I warmed up the old tire and wheel with a space heater in the utility room outside. I used a NO MAR to dismount the old tire and when I positioned the center post in the wheel bearing the bearing seal popped out! There was plenty of grease inside and I made sure there was not dirt or grit and just pushed the seal back in place and continued. It was however extremely difficult to mount the top bead. I was working the mount bar with so much force it kept popping out. I finally removed the wheel from the NO MAR and did it the old fashioned way with tire irons and my knees. I removed my new EBC rotor as I was afraid I would slip and wreck it. Finally got it mounted and a test ride proved all is well. Of course I am concerned about the wheel bearings and have order a new set from All Balls Racing.
I am wondering if the sudden temperature change caused the bearing seal to pop out. The 08 now has 133,000 miles and I have probably changed 15 front tires on it and this has never happened before.