This is somewhat informational and somewhat of a rant
I've read through forums that this is a common issue with the Zs and has a TSB out for it, and most people got it covered under the drivetrain warranty.
The dealership I went to though did not cover it, they knew what the problem was and how to fix it yet wouldn't tell me if it's covered under the warranty UNTIL they regreased the axle, THEN they told me it was $150...
lesson learned and a warning to all
UPDATE: CALLED NISSAN and they agreed to cover it under warranty and reimbursed me