I did the rear brakes last night and used the special cube tool to twist the rear caliper pistons back into the place. The first one was easy, it fully retracted and eventually stopped. The second one, easily retracted as I screwed it in, but it never did snug up. I could just keep spinning it after it was fully retracted. I eventually just lined up the piston grooves with inside caliper nipple and finished the installation. Does anyone know if I should be concerned that the piston did not eventually snug up in the retracted position?