Did a full front brake service last week with a full brake fluid flush and noticed the rears were low as well at just over 1/8" remaining. (Fronts were just under 1/8") Definitely could have got 6 more months out of them but it just bugged me all week that my brakes were not 100% so ordered everything from FCP and did the full rear brake service today with rotors, pads and sensor. Now my brake service is a complete 100%.
The 25mm spacers wanted to be a problem, they had set up a homestead on the rear hub/rotor