You have the wrong dealer installed locks and there was a tsb for the early Z's. I had the same problem and bought replacement locks only have them break because the dealer was still using the wrong locks. I went to the dealer and asked them to replace them and they said well we have to prove that we installed them? WTF?? What we're these guys smoking!! They thought I bought them on my own and broke them and just wanted free locks!! I left pissed and went to another dealer (Cerritos Nissan) and they were nice to just give me lugs since the correct locks were not available. I feel your frustration.
TSB: 2009 nissan 370z / 350z; accessory locking wheel nuts
Downey Nissan Service
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