i had my two rear tires get "screwed" one was in the middle the other was on the edge of the tread the one in the middle got a plug and patch the one on the edge only gets a plug. the pacth only works for the flat areas not the curves of a tire after my last service the tires were rotated to the front. much wobble. had to get the 2 road force balanced. a lot smoother at 65 but, there is a very very slight wobble. next years service they will be on the back (26,000 miles) and then in another year after that (35,000 miles) i project replacement of all.