Rear Axle Clunk (Please Report Here!)

UNKNOWN_370

Buddy, you are beating a dead horse. Besides they are real hard on newbs here. Also there's a lot of cliquing between members so if you keep talking about it they are going to gang up on you and eat you alive.
Get the axle greased. Then drive it. Worst case scenario, it will need grease in 3 or 4 years. The Z is one of the most reliable sports cars out there.
I've owned quite a few nissans. They all have quirks. They all have something going on that's alarming compared to other brands. I had a 98 altima with tranny jump. I would put it in gear and it would pop. Took it to 3 mechanics. They couldn't find anything. I had a 240sx that did the same thing. I sold the 240sx before I could even care. But the altima, I was keeping so I checked it out. The mechanic told me some wise words that hold true 3 more nissans later. He said "In all the years I worked on nissans, they have quirks I can't exxplain, weird abnormalities, but they will never break down." Out of 5 nissans, and probably a combined million miles. I had one breakdown on the alternator on the 98 altima. Nothing else. You will get used to your car. I don't have a Z yet, I have a G which shares most components minus some extra peformance parts and short chassis.
I'm sure you will be ok. Just get some grease bro.