Good call. I know zero about Caddys and thought the car was called ATS-V did not know that it was a separate car than the ATS. Glad I got the part numbers in there. They are the J55 Brembo's for the Turbo 4 cylinder ATS. As far as Z23 instead of Z26 I have no clue. Lack of sleep I guess. I thought I ordered Z26.