I just put a new Michelin Pilot Road 4 150/70ZR-17 on the rear. The old Michelin Pilot Road 4 went 17,310 mostly commuting miles. It was squared off and down to the wear bars. Not bad mileage considering the coarse chip rock roads here in Texas. Phil, I neglected to look at the manufacturing date of the old tire, but I installed it on 8/2/2015. My new tire was manufactured on 35-2015, about the same time as I installed it's predecessor.
Go Pats!
Go Pats!